Fait général: 6704 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 6704 is the number of rooted 8-hexes.
Culture générale: 6704 is an unremarkable number.
Date historique: May 9th is the day in 1904 that the steam locomotive City of Truro becomes the first steam engine in Europe to exceed 100 mph (160 km/h).