general_fact: 2581 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
math_fact: 2581 is the smallest number whose square begins with three 6's.
trivia: 2581 is a boring number.
historical_date: January 24th is the day in 1438 that the Council of Basel suspends Pope Eugene IV as Prelate of Ethiopia, arrives at Massawa from Goa.