Rüdiger Gamm (born July 10, 1971) is a German "mental calculator". He is known as the most spectacular mental athlete ever. He attained the ability to mentally evaluate large arithmetic expressions at the age of 21. He can also speak backwards, and calculate calendars. Featured on the Discovery Channel program The Real Superhumans, he was examined by Allan Snyder, an expert on savants, who concluded that Gamm's ability was not a result of savant syndrome but connected to genetics.
In terms of mental calculations, Rüdiger's most notable talent is the ability to memorize large powers. In the 2008 Mental Calculation World Cup in Leipzig, he recited 81100, which took approximately 2 minutes and 30 seconds. In the tournament itself, he performed strongly, finishing in 5th position overall. He also held a seminar in 2012 at the BOLDTalks event at DUCTAC (Dubai).