Fait général: 6819 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 6819 is 20457 / 3, and each digit is contained in the equation exactly once.
Culture générale: 6819 is an unremarkable number.
Date historique: September 1st is the day in 1873 that Cetshwayo ascends to the throne as king of the Zulu nation following the death of his father Mpande.