Fatto generale: 16657 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 16657 is an uninteresting number.
Trivia: 16657 is an uninteresting number.
Data storica: August 8th is the day in 1709 that Bartolomeu de Gusmão demonstrates the lifting power of hot air in an audience before the King of Portugal in Lisbon.