List of Famous people who are 21

Jack Douglas is an American record producer. He is known for his work with John Lennon and Yoko Ono, Patti Smith, Cheap Trick, and New York Dolls, among other rock artists in the 1970s and 1980s, notably producing three successful albums for Aerosmith.

Steven S. DeKnight is an American screenwriter, television producer, and director. He is best known for being the creator, head writer, and executive producer of the Starz series Spartacus, including Spartacus: Blood and Sand, Spartacus: Gods of the Arena, Spartacus: Vengeance, and Spartacus: War of the Damned.

Nicholas John Pippenger is a researcher in computer science. He has produced a number of fundamental results many of which are being widely used in the field of theoretical computer science, database processing and compiler optimization. He has also achieved the rank of IBM Fellow at Almaden IBM Research Center in San Jose, California. He has taught at the University of British Columbia in Vancouver, British Columbia, Canada and at Princeton University in the US. In the Fall of 2006 Pippenger joined the faculty of Harvey Mudd College.

David G. Lowe is a Canadian computer scientist working for Google as a Senior Research Scientist. He was a former professor in the Computer Science Department at the University of British Columbia and New York University.

Duncan Tucker is an American film director and screenwriter.

Violeta Ivanova is a Bulgarian astronomer.