Many official numbers are random or use other numbers as a base, the best example of this is Ultimate Marvel. 1610 is the swapped numbers of 616 with a 0 to differentiate it from the already existing 161. In addition, many universes have also been designated with numbers by fans with various methods for the numbering, such as the birth date of an important Marvel staff member (artist Nelson Ribeiro for the Transformers U.S. Universe, Earth-91274) or the spelling of a name with a touch-tone phone (Animated Silver Surfer Earth, 936652, spells out Zenn-La).