Numbers / 423

The Number 423

423 is composite: factorization 3^2 × 47. That gives 423 exactly 6 divisors: 1, 3, 9, 47, 141, 423. 423's proper divisors total just 201, 222 short of 423, the deficient case most of 423's neighbors share too. 423 has a digit sum of 9; for 423, the digital root works out to 9. 423: 3, 9 all divide 423 evenly, out of 2-12. 423 is 110100111 in binary and 1A7 in hex; as a Roman numeral it's CDXXIII.