13 (number)

13 (disambiguation)13 February 2012 January 2026 13 tredecimal prime 6th 1, 13 Hebrew numeral י"ג Babylonian numeral 𒌋𒐗 13 (thirteen) is the natural number following 12 and preceding 14. Folklore surrounding the number 13 appears in many cultures around the world: one theory is that this is due to the cultures employing lunar-solar calendars (there are approximately 12.41 lunations per solar year, and hence 12 "true months" plus a smaller, and often portentous, thirteenth month). This can be witnessed, for example, in the "Twelve Days of Christmas" of Western European tradition.Frazier, King of the Bean, and the Festival of Fools. Cited in Thompson, Tok. 2002. The thirteenth number: Then, there/ here and now. Studia Mythological Slavica 5, 145–159. In mathematics The number 13 is a prime number, happy numberSloane's A007770 : Happy numbers https://oeis.org/A007770 2016-06-01 The On-Line Encyclopedia of Integer Sequences OEIS Foundation and a lucky number.A000959 Lucky numbers. (Formerly M2616 N1035) https://oeis.org/A000959 2018-10-31 OEIS: The On-Line Encyclopedia of Integer Sequences OEIS Foundation It is a twin prime with 11, as well as a cousin prime with 17. It is the second of the only three known Wilson primes: 5, 13, and 563.A007540 wilson primes A 13-sided regular polygon is called a tridecagon. 13 is a Fibonacci number and an ordered Bell number.Those Fascinating Numbers J. M. de Koninck American Mathematical Society 2009 9780821886311 https://books.google.com/books?id=qYuC1WsDKq8C&pg=PA4 4 In Sanskrit prosody, there are 13 combinations of light and heavy syllables that add to six morae, since 13 is a Fibonacci number. Singh Parmanand 10.1016/0315-0860(85)90021-7 3 Historia Mathematica 803579 229–244 The so-called Fibonacci numbers in ancient and medieval India 12 1985 Because 13 is an ordered bell number, there are 13 orders in which a three-way horse race can finish, allowing for ties. List of basic calculations Multiplication12345678910111213141516171819202122232425501001000(13)x13263952657891104117130143156169182195208221234247260273286299312325650130013000 Division12345678910111213141513 ÷ x136.54.33.252.62.161.8571421.6251.41.31.181.08310.92857140.86x ÷ 130.0769230.1538460.2307690.3076920.3846150.4615380.5384610.6153840.6923070.7692300.8461530.92307611.0769231.153846 Exponentiation123456789101113x13169219728561371293482680962748517815730721106044993731378584918491792160394037x13181921594323671088641220703125130606940169688901040754975581388825418658283291000000000000034522712143931 In languages Grammar In all Germanic languages, 13 is the first compound number; the numbers 11 and 12 have their own names.Why do we say "Eleven" and "Twelve" instead of "Firsteen" and "Seconteen"? Notes and Queries guardian.co.uk https://www.theguardian.com/notesandqueries/query/0,5753,-18923,00.html 2026-08-06 www.theguardian.com Folklore In Germany, according to an old tradition, 13 (de dreizehn), as the first compound number, was the first number written in digits; the numbers 0 (de null) through 12 (de zwölf) were spelled out. The Duden (the German standard dictionary) now calls this tradition (which was actually never written down as an official rule) outdated and no longer valid, but many writers still follow it.https://www.duden.de/sprachwissen/sprachratgeber/Schreibung-von-Zahlen-0 Duden Schreibung von Zahlen bis 12 www.duden.de de 2020-03-23 In English Thirteen is one of two numbers within the teen numerical range (13–19), along with fifteen, not derived by cardinal numeral (three) and the teen suffix; instead, it is derived from the ordinal numeral (third).October 2025 In religion Islam In Shia, 13 signifies the 13th day of the month of Rajab (the Lunar calendar), which is the birth of Imam Ali.SMF 2025-01-15 SMF celebrates the 13th of Rajab: The Birth of Imam Ali https://www.shiamuslimfoundation.com/post/smf-celebrates-the-13th-of-rajab-the-birth-of-imam-ali 2026-08-06 SMF en Catholicism In Catholic devotional practice, the number thirteen is also associated with Saint Anthony of Padua, since his feast day falls on June 13. A traditional devotion called the Thirteen Tuesdays of St. Anthonyhttp://www.shrineofstanthony.org/novena-to-st-anthony.htm The Shrine of St. Anthony shrineofstanthony.org July 13, 2011 November 12, 2011 https://web.archive.org/web/20111112102059/http://www.shrineofstanthony.org/novena-to-st-anthony.htm dead involves praying to the saint every Tuesday over a period of thirteen weeks. Another devotion, St. Anthony's Chaplet, consists of thirteen decades of three beads each.http://www.catholicculture.org/culture/liturgicalyear/prayers/view.cfm?id=1236 Liturgical Year: Prayers: Chaplet of St. Anthony catholicculture.org Sikhism According to famous Sakhi (evidence) or the story of Guru Nanak Dev Ji, when he was an accountant at a town of Sultanpur Lodhi, he was distributing groceries to people. When he gave groceries to the 13th person, he stopped because in Gurmukhi and Hindi the word 13 is called terah, which means yours. And Guru Nanak Dev Ji kept saying, "Yours, yours, yours..." remembering God. People reported to the emperor that Guru Nanak Dev Ji was giving out free food to the people. When treasures were checked, there was more money than before.Shackle Christopher Mandair Arvind-Pal Singh Teachings of the Sikh Gurus: Selections from the Sacred Scriptures Routledge 2005 xvii 978-0-415-26604-8 According to the traditional accounts (janamsakhis), while working as a storekeeper in Sultanpur, Nanak reached the number thirteen (terah), which means 'thine' in Hindi/Punjabi. Caught in a divine trance, he began repeating 'Terah, terah' (I am Thine, O Lord), distributing the remaining provisions to all without count. Judaism In Judaism, 13 signifies the age at which a boy matures and becomes a Bar Mitzvah, i.e., a full member of the Jewish faith (counts as a member of Minyan). Wicca A common tradition in the religion Wicca holds that the number of members for a coven is ideally thirteen, though this tradition is not universal.Raymond Buckland Buckland's Complete Book of Witchcraft Llewellyn 1986 St. Paul, MN https://books.google.com/books?id=fr0pse0LBK0C 17–18–53 9780875420509 2022-02-17 Luck Bad Triskaidekaphobia vertical 250 Many buttons (4187599550).jpg Buttons in an elevator show that floor numbers skip from 12 to 14, to avoid labeling a floor as the thirteenth. The number 13 is considered an unlucky number in some countries.http://urbanlegends.about.com/cs/historical/a/friday_the_13th.htm Why Is Friday the 13th Unlucky? - History and Folklore David Emery About.com Entertainment August 1, 2011 January 16, 2017 https://web.archive.org/web/20170116161555/http://urbanlegends.about.com/cs/historical/a/friday_the_13th.htm dead The end of the Mayan calendar's 13th Baktun was superstitiously feared as a harbinger of the apocalyptic 2012 phenomenon.https://www.usatoday.com/tech/science/discoveries/story/2011-11-24/mexico-apocalypse-2012-mayans/51387348/1 USA Today Most Popular E-mail Newsletter November 24, 2011 Fear of the number 13 has a specifically recognized phobia, triskaidekaphobia, a word first recorded in 1911.triskaidekaphobia The superstitious sufferers of triskaidekaphobia try to avoid bad luck by keeping away from anything numbered or labelled thirteen. As a result, companies and manufacturers use another way of numbering or labelling to avoid the number, with hotels and tall buildings being conspicuous examples (thirteenth floor).Fleischman Sid The 13th Floor: A Ghost Story https://www.washingtonpost.com/wp-dyn/content/article/2007/08/18/AR2007081800890.html The Washington Post July 26, 2008 August 19, 2007 It is also considered unlucky to have thirteen guests at a table. Friday the 13th has been considered an unlucky day. There are a number of theories as to why the number thirteen became associated with bad luck, but none of them have been accepted as likely. The Last Supper Jesus Christ's Last Supper, there were thirteen people around the table, counting Christ and the twelve apostles. Some believe this is unlucky because one of those thirteen, Judas Iscariot, was the betrayer of Jesus Christ. From the 1890s, a number of English language sources relate the "unlucky" thirteen to an idea that at the Last Supper, Judas, the disciple who betrayed Jesus, was the 13th to sit at the table.Cecil Adams (1992-11-06). "Why is the number 13 considered unlucky?". The Straight Dope. Retrieved 2011-05-13. Knights Templar On Friday, 13 October 1307, King Philip IV of France ordered the arrest of the Knights Templar, and most of the knights were tortured and killed. Full moons A year with 13 full moons instead of 12 posed problems for the monks in charge of the calendars. "This was considered a very unfortunate circumstance, especially by the monks who had charge of the calendar of thirteen months for that year, and it upset the regular arrangement of church festivals. For this reason, thirteen came to be considered an unlucky number."http://www.space.com/9566-strange-story-sunday-blue-moon.html The Really Strange Story Behind Sunday's Blue Moon Space.com November 19, 2010 However, a typical century has about 37 years that have 13 full moons, compared to 63 years with 12 full moons, and typically every third or fourth year has 13 full moons.Cooley Keith http://home.hiwaay.net/~krcool/Astro/moon/fullmoonU.htm Full Moons 1900-2100 2008 Johns Hopkins University Applied Physics Laboratory August 1, 2011 June 24, 2011 https://web.archive.org/web/20110624071327/http://home.hiwaay.net/~krcool/Astro/moon/fullmoonU.htm dead A suppressed lunar cult In ancient cultures, the number 13 represented femininity, because it corresponded to the number of lunar (menstrual) cycles in a year (13 × 28 364 days). The theory is that, as the solar calendar triumphed over the lunar, the number thirteen became anathema.Stan Gooch, Guardians of the Ancient Wisdom (1980) Hammurabi's code There is a myth that the earliest reference to thirteen being unlucky or evil is in the Babylonian Code of Hammurabi (circa 1780 BC), where the thirteenth law is said to be omitted. In fact, the original Code of Hammurabi has no numeration. The translation by L.W. King (1910), edited by Richard Hooker, omitted one article: If the seller have gone to (his) fate (i. e., have died), the purchaser shall recover damages in said case fivefold from the estate of the seller. Other translations of the Code of Hammurabi, for example the translation by Robert Francis Harper, include the 13th article.The Code of Hammurabi (Harper translation) Good Lucky Thirteen (disambiguation) thumb|right|American singer-songwriter Taylor Swift considers the number 13 to be lucky and references it throughout her work.https://www.yahoo.com/entertainment/why-taylor-swift-loves-number-235859466.html The full history of Taylor Swift and her 'lucky number' 13 Yahoo August 11, 2025 In France, 13 was traditionally considered a lucky number in France prior to the First World War, and was used in numerical form as a good luck symbol on postcards and charms.Owen Davies A Supernatural War: Magic, Divination, and Faith During the First World War 2018 Oxford Oxford University Press 9780198794554 136 In Italy, 13 was the lucky number in the Italian football pools (Totocalcio). The Italian expression it "fare tredici" (literally, "make thirteen") means to hit the jackpot.Tredici: Definizione e significato di tredici https://dizionari.corriere.it/dizionario_italiano/T/tredici.shtml dizionari.corriere.it Dizionario di Italiano il Sabatini Coletti https://web.archive.org/web/20190622091617/https://dizionari.corriere.it/dizionario_italiano/T/tredici.shtml 22 June 2019 it Colgate University also considers 13 a lucky number. The university was founded in 1819 by 13 men with 13 dollars, 13 prayers and 13 articles.http://www.colgate.edu/DesktopDefault1.aspx?tabid=497&pgID=1200 Colgate: History & Traditions Colgate University September 1, 2007 https://web.archive.org/web/20070814204636/http://www.colgate.edu/DesktopDefault1.aspx?tabid=497&pgID=1200 August 14, 2007 (To this day, members of the Colgate community consider the number 13 a good omen.) In fact, the campus address is 13 Oak Drive in Hamilton, New York, and the male a cappella group is called the Colgate 13. Other A baker's dozen, devil's dozen,Definition of DEVIL'S DOZEN https://www.merriam-webster.com/dictionary/devil%27s+dozen 2022-05-09 www.merriam-webster.com en long dozen, or long measure is 13, one more than a standard dozen. The thirteenth loaf is called the vantage loaf because it is considered advantageous overall to get 13 loaves for the price of 12.2011 Vantage loaf https://www.oxfordreference.com/view/10.1093/acref/9780199829941.001.0001/acref-9780199829941-e-49852 Green's Dictionary of Slang Oxford University Press 978-0-19-982994-1 22 July 2020 In a tarot card deck, XIII is the card of Death, usually picturing the Pale Horse with its rider. The number 13 is a recurring motif in American heraldry, referencing the 13 Colonies that formed the United States. Age 13 In Judaism, thirteen signifies the age at which a boy matures and becomes a Bar Mitzvah, i.e., a full member of the Jewish faith."Origins of the Bar/Bat Mitzvah". ReformJudaism.org. October 19, 2012. “Today in almost all non-Orthodox congregations, all children mark symbolic entry into Jewish adulthood through b'nai mitzvah (bar or bat mitzvah) at age 13.” Thirteen is the minimum age of consent in Argentina, Burkina Faso, Niger, and two Mexican states. On many social media platforms in the United States, 13 is the standard minimum age to be allowed to create an account in compliance with the Children's Online Privacy Protection Act (COPPA). This is the age at which the Entertainment Software Rating Board (ESRB) assesses for T-rated games and the Motion Picture Association recommends movies with a PG-13 rating. In sports The number 13 was not used in the Indianapolis 500 from 1915 to 2002. It was not permitted for use between 1926 and 2002. In 2009, E. J. Viso, driving for HVM Racing in the 2009 IndyCar Series season, drove a green number 13 car full-time, despite terrible superstitions about it in motorsports. The number 13 was not used in Formula One from 1977 to 2013. In rugby league: The jersey number 13 is worn by the starting loose forward or lock forward in most competitions. An exception is in the Super League, which uses static squad numbering. In rugby union, the jersey number 13 is worn by the outside centre. In triathlon, the number 13 is not used. As such, the numbering goes 11, 12, 14, 15 under the current numbering system. In cycle sport events like the Tour de France, riders assigned the number 13 will often wear their race bib upside down. References zero Category:Integers Category:Numerology Category:Superstitions about numbers Category:Prime numbers