Cognomen Ivach (Иваш 
, Ivach 
) , all around the world, is a rare surname. The surname Ivach is characteristic of Belarus, where it is a rare surname, Kyrgyzstan, where it is a very rare surname, and Kazakhstan. Measured by absolute frequency, it most frequently occurs in India, Belarus, and Russia. Much less frequently, Ivach is the forename as well as the last name.