Family name Рейген (Reigen 
, Рейген 
) , around the globe, is a rare cognomen. The cognomen Рейген is habitual in Japan, where it is a very rare surname, Indonesia, and Ukraine, where it is an extremely rare surname. In absolute terms, it most frequently occurs in Japan, Indonesia, and the United States. Also, Рейген is the forename as well as the last name.