Fatto generale: 54166 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 54166 is an uninteresting number.
Trivia: 54166 is an uninteresting number.
Data storica: April 19th is the day in 1782 that John Adams secures the Dutch Republic's recognition of the United States as an independent government.