Fatto matematico: 713 is the number of commutative monoids of order 7 with 4 idempotents.
Trivia: 713 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: December 13th is the day in 1979 that the Canadian Government of Prime Minister Joe Clark is defeated in the House of Commons, prompting the 1980 Canadian election.