Fatto matematico: 1579 is the smallest prime that remains prime when preceded and followed by one, two, three, or four 9's.
Trivia: 1579 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: April 27th is the day in 1904 that the Australian Labor Party becomes the first such party to gain national government, under Chris Watson.