Numbers / 351

The Number 351

351 is composite: factorization 3^3 × 13. That gives 351 exactly 8 divisors: 1, 3, 9, 13, 27, 39, 117, 351. 351's proper divisors total just 209, 142 short of 351, the deficient case most of 351's neighbors share too. 351 is also the 26th triangular number, the sum of 1 through 26. 351 has a digit sum of 9; for 351, the digital root works out to 9. 351: 3, 9 all divide 351 evenly, out of 2-12. 351 is 101011111 in binary and 15F in hex; as a Roman numeral it's CCCLI.