Numbers / 407
The Number 407
407 is composite: factorization 11 × 37. That gives 407 exactly 4 divisors: 1, 11, 37, 407. 407's proper divisors total just 49, 358 short of 407, the deficient case most of 407's neighbors share too. 407 has a digit sum of 11; for 407, the digital root works out to 2. 407: 11 all divide 407 evenly, out of 2-12. 407 is 110010111 in binary and 197 in hex; as a Roman numeral it's CDVII.