Fatto generale: 8766 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 8766 is an uninteresting number.
Trivia: 8766 is an unremarkable number.
Data storica: December 31st is the day in 1998 that the European Exchange Rate Mechanism freezes the values of the legacy currencies in the Eurozone, and establishes the value of the euro currency.