Numbers / 673

The Number 673

673 is prime: only 1 and 673 divide it evenly; the next prime after 673 is 677. 673's proper divisors total just 1, 672 short of 673, the deficient case most of 673's neighbors share too. 673 has a digit sum of 16; for 673, the digital root works out to 7. 673 shares no factor with 2-12; 673's own divisors start beyond that range. 673 is 1010100001 in binary and 2A1 in hex; as a Roman numeral it's DCLXXIII.