Fatto matematico: 456 is the number of tournaments with 7 vertices.
Trivia: 456 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: March 31st is the day in 1965 that an Iberia Airlines Convair 440 crashes into the sea on approach to Tangier, killing 47 of 51 occupants.