Numbers / 389

The Number 389

389 is prime: only 1 and 389 divide it evenly; the next prime after 389 is 397. 389's proper divisors total just 1, 388 short of 389, the deficient case most of 389's neighbors share too. 389 has a digit sum of 20; for 389, the digital root works out to 2. 389 shares no factor with 2-12; 389's own divisors start beyond that range. 389 is 110000101 in binary and 185 in hex; as a Roman numeral it's CCCLXXXIX.