Numbers / 825

The Number 825

825 is composite: factorization 3 × 5^2 × 11. That gives 825 exactly 12 divisors: 1, 3, 5, 11, 15, 25, 33, 55, 75, 165, 275, 825. 825's proper divisors total just 663, 162 short of 825, the deficient case most of 825's neighbors share too. 825 has a digit sum of 15; for 825, the digital root works out to 6. 825: 3, 5, 11 all divide 825 evenly, out of 2-12. 825 is 1100111001 in binary and 339 in hex; as a Roman numeral it's DCCCXXV.