Fatto generale: 1056 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 1056 is the area of the smallest non-square rectangle that can be tiled with integer-sided squares.
Trivia: 1056 is an unremarkable number.
Data storica: November 21st is the day in 1905 that Albert Einstein's paper, Does the Inertia of a Body Depend Upon Its Energy Content?, is published in the journal "Annalen der Physik".