Fatto matematico: 2958 is the number of multigraphs with 21 vertices and 4 edges.
Trivia: 2958 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: February 5th is the day in 1576 that Henry of Navarre abjures Catholicism at Tours and rejoins the Protestant forces in the French Wars of Religion.