Numbers / 151

The Number 151

151 is prime: only 1 and 151 divide it evenly; the next prime after 151 is 157. 151's proper divisors total just 1, 150 short of 151, the deficient case most of 151's neighbors share too. 151 is also a palindrome, since 151 reads identically forwards and backwards. 151 has a digit sum of 7; for 151, the digital root works out to 7. 151 shares no factor with 2-12; 151's own divisors start beyond that range. 151 is 10010111 in binary and 97 in hex; as a Roman numeral it's CLI.