120 (another Prime Pages' Curiosity)
 Curios: Curios Search:   Participate: GIMPS has discovered a new largest known prime number: 282589933-1 (24,862,048 digits) The largest integer n for which (n) = n/4. [Woods] 120 = 31 + 32 + 33 + 34. [Sladcik] 120^120-119^119 is prime. [Dobb] 120 is the smallest composite number of the form x! whose digit sum and x are primes. [Capelle] All primes (except 2 and 3) are of form 6*n +/- 1. Note that 120 = 6*20 is the first number such that 6n+1 or 6n-1 does not contain a prime. [Luhn] 120 is the smallest three-digit number that may be expressed as the difference between the squares of consecutive primes in two different ways (120 = 31^2 - 29^2 = 17^2 - 13^2). [King] The smallest possible sum for a set of six distinct double-digit primes such that the sum of any five is prime: {11, 13, 17, 19, 23, 37}. [Loungrides] The smallest number whose the sum of the reciprocals of its divisors is an odd prime. [Loungrides] (There are 2 curios for this number that have not yet been approved by an editor.) Prime Curios! © 2000-2019 (all rights reserved)  privacy statement   (This page was generated in 0.0288 seconds.)