Numbers / 317

The Number 317

317 is prime: only 1 and 317 divide it evenly; the next prime after 317 is 331. 317's proper divisors total just 1, 316 short of 317, the deficient case most of 317's neighbors share too. 317 has a digit sum of 11; for 317, the digital root works out to 2. 317 shares no factor with 2-12; 317's own divisors start beyond that range. 317 is 100111101 in binary and 13D in hex; as a Roman numeral it's CCCXVII.