Numbers / 520

The Number 520

520 is composite: factorization 2^3 × 5 × 13. That gives 520 exactly 16 divisors: 1, 2, 4, 5, 8, 10, 13, 20, 26, 40, 52, 65, 104, 130, 260, 520. 520's proper divisors total 740, 220 more than 520 itself, so 520 is abundant. 520 has a digit sum of 7; for 520, the digital root works out to 7. 520: 2, 4, 5, 8, 10 all divide 520 evenly, out of 2-12. 520 is 1000001000 in binary and 208 in hex; as a Roman numeral it's DXX.