The 47 Society

As detailed on The Other Wiki here, the number 47 has become an in joke among groups of mathematicians and screenwriters, improbable as the crossover may seem.
 * One of the biggest users is theStar Trek franchise, to the point of having a page on its wiki.
 * The protagonist of the Hitman series.
 * Subverted by HK-47 from Knights of the Old Republic, who is named after the AK-47. Same goes for the multitude of fictional guns with 47 in the name.
 * As most (all?) the writers of the League of Intergalactic Cosmic Champions were Star Trek fans 47s were a big in joke there too.