Numbers / 73

The Number 73

73 is prime: only 1 and 73 divide it evenly; the next prime after 73 is 79. 73's proper divisors total just 1, 72 short of 73, the deficient case most of 73's neighbors share too. 73 has a digit sum of 10; for 73, the digital root works out to 1. 73 shares no factor with 2-12; 73's own divisors start beyond that range. 73 is 1001001 in binary and 49 in hex; as a Roman numeral it's LXXIII.