Numbers / 127

The Number 127

127 is prime: only 1 and 127 divide it evenly; the next prime after 127 is 131. 127's proper divisors total just 1, 126 short of 127, the deficient case most of 127's neighbors share too. 127 has a digit sum of 10; for 127, the digital root works out to 1. 127 shares no factor with 2-12; 127's own divisors start beyond that range. 127 is 1111111 in binary and 7F in hex; as a Roman numeral it's CXXVII.