Cognomen 信康 (Nobuyasu 
, 信康 ) , in the world, is quite a rare surname. The family name 信康 is habitual in Japan, where it is quite a rare surname, Hungary, where it is a very rare surname, and China. Not in comparison with a country's population, it is commonest in Japan, China, and Brazil. More prevalently, 信康 is the forename as well as the last name.