Fatto generale: 6428 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 6428 is a boring number.
Trivia: 6428 is an uninteresting number.
Data storica: August 6th is the day in 2001 that Erwadi fire incident, 28 mentally ill persons tied to chain were burnt to death at a faith based institution at Erwadi, Tamil Nadu.