<P> Akira Haraguchi (原口 證, Haraguchi Akira) (born 1946, Miyagi Prefecture), a retired Japanese engineer, is known for memorizing and reciting digits of pi . </P> <P> He holds the current unofficial world record (100,000 digits) in 16 hours, starting at 9 a.m (16: 28 GMT) on October 3, 2006 and having recited up to 83,431 digits by nightfall, stopping with digit number 100,000 at 1: 28 a.m. on October 4, 2006 . The event was filmed in a public hall in Kisarazu, east of Tokyo, where he had five - minute breaks every two hours to eat onigiri to keep up his energy levels . Even his trips to the toilet were filmed to prove that the exercise was legitimate . Haraguchi's previous world record (83,431), was performed from July 1, 2005 to July 2, 2005 . On Pi Day, 2015, he claimed to be able to recite 111,701 digits . </P> <P> Despite Haraguchi's efforts and detailed documentation, the Guinness World Records have not yet accepted any of his records set . </P>

Who held the record for most memorized digits the longest