Hecho matemático: 2551 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 2551 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fecha histórica: December 25th is the day in 1946 that the first in Europe artificial, self-sustaining nuclear chain reaction is initiated within Soviet nuclear reactor F-1.