Cognomen 里根 (Reagan 
, Regan , 里根 
) , in the entire world, is a common family name. The cognomen 里根 is characteristic of Ireland, where it is quite a common surname, Fiji, and Isle of Man (explore the name in all countries). Not in comparison with a country's population, it is the most numerous in the United States, the United Kingdom, and Ireland. Likewise, 里根 is the forename as well as the last name.