Numbers / 569

The Number 569

569 is prime: only 1 and 569 divide it evenly; the next prime after 569 is 571. 569's proper divisors total just 1, 568 short of 569, the deficient case most of 569's neighbors share too. 569 has a digit sum of 20; for 569, the digital root works out to 2. 569 shares no factor with 2-12; 569's own divisors start beyond that range. 569 is 1000111001 in binary and 239 in hex; as a Roman numeral it's DLXIX.