Numbers / 39

The Number 39

39 is composite: factorization 3 × 13. That gives 39 exactly 4 divisors: 1, 3, 13, 39. 39's proper divisors total just 17, 22 short of 39, the deficient case most of 39's neighbors share too. 39 has a digit sum of 12; for 39, the digital root works out to 3. 39: 3 all divide 39 evenly, out of 2-12. 39 is 100111 in binary and 27 in hex; as a Roman numeral it's XXXIX.