Hecho general: 6511 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 6511 is a number n whose sum of the factorials of its digits is equal to p(n).
Trivia: 6511 is an unremarkable number.
Fecha histórica: October 28th is the day in 1628 that the Siege of La Rochelle, which had lasted for 14 months, ends with the surrender of the Huguenots.