Surname Райку (Rajku 
, Raiku 
, Rayku ) , in the entire world, is a rare family name. The family name Райку is characteristic of Albania, where it is quite a common surname, Greece, where it is a rare surname, and Kazakhstan, where it is a very rare surname. Measured by absolute frequency, it most frequently occurs in Albania, Russia, and India. More frequently, Райку is the forename as well as the last name.