Fatto matematico: 797 is the number of functional graphs on 9 vertices.
Trivia: 797 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: March 7th is the day in 1850 that Senator Daniel Webster gives his "Seventh of March" speech endorsing the Compromise of 1850 in order to prevent a possible civil war.