Numbers / 279

The Number 279

279 is composite: factorization 3^2 × 31. That gives 279 exactly 6 divisors: 1, 3, 9, 31, 93, 279. 279's proper divisors total just 137, 142 short of 279, the deficient case most of 279's neighbors share too. 279 has a digit sum of 18; for 279, the digital root works out to 9. 279: 3, 9 all divide 279 evenly, out of 2-12. 279 is 100010111 in binary and 117 in hex; as a Roman numeral it's CCLXXIX.