Fatto generale: 6508 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 6508 is an unremarkable number.
Trivia: 6508 is an uninteresting number.
Data storica: October 25th is the day in 1944 that the USS Tang under Richard O'Kane (the top American submarine captain of World War II) is sunk by the ship's own malfunctioning torpedo.