Fatto generale: 25456 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 25456 is a boring number.
Trivia: 25456 is an uninteresting number.
Data storica: September 10th is the day in 1419 that John the Fearless, Duke of Burgundy is assassinated by adherents of the Dauphin, the future Charles VII of France.