Fatto generale: 66431 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 66431 is an uninteresting number.
Trivia: 66431 is an unremarkable number.
Data storica: November 17th is the day in 1968 that Alexandros Panagoulis is condemned to death for attempting to assassinate Greek dictator George Papadopoulos.