Cognomen केतन (Ketan 
, केतन ) , in the world, is quite a rare last name. The last name केतन is characteristic of Papua New Guinea, where it is quite a rare surname, New Zealand, where it is a rare surname, and Oman. Not in comparison with a country's population, it is the most numerous in India, Ethiopia, and Indonesia. More prevalently, केतन is the forename as well as the last name.