“The human computer” Indian math wizard Shakuntala Devi made it into the 1982 Guinness Book of World Records when she multiplied two randomly selected 13-digit numbers (7,686,369,774,870 × 2,465,099,745,779) to give, within seconds, the 26-digit solution: 18,947,668,177,995,426,462,773,730 (Pandya, 2013).

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