Numbers / 443

The Number 443

443 is prime: only 1 and 443 divide it evenly; the next prime after 443 is 449. 443's proper divisors total just 1, 442 short of 443, the deficient case most of 443's neighbors share too. 443 has a digit sum of 11; for 443, the digital root works out to 2. 443 shares no factor with 2-12; 443's own divisors start beyond that range. 443 is 110111011 in binary and 1BB in hex; as a Roman numeral it's CDXLIII.