Numbers / 961

The Number 961

961 is composite: factorization 31^2. That gives 961 exactly 3 divisors: 1, 31, 961. 961's proper divisors total just 32, 929 short of 961, the deficient case most of 961's neighbors share too. 961 is also a perfect square, since 31² = 961. 961 has a digit sum of 16; for 961, the digital root works out to 7. 961 shares no factor with 2-12; 961's own divisors start beyond that range. 961 is 1111000001 in binary and 3C1 in hex; as a Roman numeral it's CMLXI.