Last name 衍壬 (衍壬 
) , in all the world, is a very rare cognomen. The cognomen 衍壬 is characteristic of Eastern Asia, particularly China, where it is an extremely rare surname. More prevalently, 衍壬 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 衍壬 | China |