Last name Irau (Irau 
) , across the world, is a rare cognomen. The surname Irau is habitual in Papua New Guinea, where it is quite a rare surname, Mexico, where it is a very rare surname, and Venezuela, where it is an extremely rare surname. In absolute terms, it most frequently occurs in Papua New Guinea, Mexico, and India. Much less frequently, Irau is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Irau | Mexico, United States, Papua New Guinea, India, Brazil |