154 (number)

154 1, 2, 7, 11, 14, 22, 77, 154 154 (one hundred [and] fifty-four) is the natural number following 153 and preceding 155. In mathematics 154 is a nonagonal number.https://oeis.org/A001106 Sloane's A001106 : 9-gonal (or enneagonal or nonagonal) numbers The On-Line Encyclopedia of Integer Sequences OEIS Foundation 2016-05-28 Its factorization makes 154 a sphenic number. There is no integer with exactly 154 coprimes below it, making 154 a noncototient, nor is there, in base 10, any integer that added up to its own digits yields 154, making 154 a self number 154 is the sum of the first six factorials, if one starts with and assumes that . With just 17 cuts, a pancake can be cut up into 154 pieces (Lazy caterer's sequence).https://oeis.org/A000124 Sloane's A000124 : Central polygonal numbers (the Lazy Caterer's sequence) The On-Line Encyclopedia of Integer Sequences OEIS Foundation 2016-05-28 The distinct prime factors of 154 add up to 20, and so do the ones of 153, hence the two form a Ruth-Aaron pair. 154! + 1 is a factorial prime. References Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group. (1987): 140 - 141 External links Virtual Science: Number 154 https://web.archive.org/web/20170630152741/http://www.virtuescience.com/154.html 2017-06-30 1 Category:Integers