Numbers / 210

The Number 210

210 is composite: factorization 2 × 3 × 5 × 7. That gives 210 exactly 16 divisors: 1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 35, 42, 70, 105, 210. 210's proper divisors total 366, 156 more than 210 itself, so 210 is abundant. 210 is also the 20th triangular number, the sum of 1 through 20. 210 has a digit sum of 3; for 210, the digital root works out to 3. 210: 2, 3, 5, 6, 7, 10 all divide 210 evenly, out of 2-12. 210 is 11010010 in binary and D2 in hex; as a Roman numeral it's CCX.