Numbers / 529

The Number 529

529 is composite: factorization 23^2. That gives 529 exactly 3 divisors: 1, 23, 529. 529's proper divisors total just 24, 505 short of 529, the deficient case most of 529's neighbors share too. 529 is also a perfect square, since 23² = 529. 529 has a digit sum of 16; for 529, the digital root works out to 7. 529 shares no factor with 2-12; 529's own divisors start beyond that range. 529 is 1000010001 in binary and 211 in hex; as a Roman numeral it's DXXIX.