Numbers / 543

The Number 543

543 is composite: factorization 3 × 181. That gives 543 exactly 4 divisors: 1, 3, 181, 543. 543's proper divisors total just 185, 358 short of 543, the deficient case most of 543's neighbors share too. 543 has a digit sum of 12; for 543, the digital root works out to 3. 543: 3 all divide 543 evenly, out of 2-12. 543 is 1000011111 in binary and 21F in hex; as a Roman numeral it's DXLIII.