Fatto generale: 2806 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 2806 is the number of semigroups of order 6 with 2 idempotents.
Trivia: 2806 is an unremarkable number.
Data storica: September 6th is the day in 1847 that Henry David Thoreau leaves Walden Pond and moves in with Ralph Waldo Emerson and his family in Concord, Massachusetts.