Numbers / 609

The Number 609

609 is composite: factorization 3 × 7 × 29. That gives 609 exactly 8 divisors: 1, 3, 7, 21, 29, 87, 203, 609. 609's proper divisors total just 351, 258 short of 609, the deficient case most of 609's neighbors share too. 609 has a digit sum of 15; for 609, the digital root works out to 6. 609: 3, 7 all divide 609 evenly, out of 2-12. 609 is 1001100001 in binary and 261 in hex; as a Roman numeral it's DCIX.