Numbers / 30

The Number 30

30 is composite: factorization 2 × 3 × 5. That gives 30 exactly 8 divisors: 1, 2, 3, 5, 6, 10, 15, 30. 30's proper divisors total 42, 12 more than 30 itself, so 30 is abundant. 30 has a digit sum of 3; for 30, the digital root works out to 3. 30: 2, 3, 5, 6, 10 all divide 30 evenly, out of 2-12. 30 is 11110 in binary and 1E in hex; as a Roman numeral it's XXX.