246

Additionally, 246 is: an untouchable number. palindromic in bases 5 (14415), 9 (3039), 40 (6640), 81 (3381), 122 (22122) and 245 (11245). a Harshad number in bases 2, 3, 6, 7, 9, 11 (and 15 other bases). the smallest number N for which it is known that there is an infinite number of prime gaps no larger than N.