Igor Shelushkov

Igor Alexeyevich Shelushkov (born c. 1946 – ?) was a Soviet mental calculator. He mentally extracted roots of large numbers and calculated the number of syllables and characters in a given verse by listening. Shelushkov was featured in the 1968 Soviet popular science film Seven Steps Beyond the Horizon, where he mentally extracted the sixth root of a 12-digit number and the 77th root of another multi-digit number.[1] Shelushkov also competed with the Soviet third generation computer Mir. He extracted the 77th root of a 148-digit number in 18 seconds, while it took about 10 minutes to program the related operation for computer.[2]

Shelushkov was a postgraduate at Gorki Polytechnic Institute (now Nizhny Novgorod State Technical University). According to Shelushkov, he used the memorized logarithmic table for calculations.[2] His abilities were mentioned by Russian mathematician Vladimir Tvorogov, who attended one of his performances,[3] and by psychologist Artur Petrovsky. Shelushkov's subsequent fate is unclear.