Numbers / 839

The Number 839

839 is prime: only 1 and 839 divide it evenly; the next prime after 839 is 853. 839's proper divisors total just 1, 838 short of 839, the deficient case most of 839's neighbors share too. 839 has a digit sum of 20; for 839, the digital root works out to 2. 839 shares no factor with 2-12; 839's own divisors start beyond that range. 839 is 1101000111 in binary and 347 in hex; as a Roman numeral it's DCCCXXXIX.