About D. R. Kaprekar
Dattatreya Ramchandra Kaprekar (Marathi: दत्तात्रेय रामचंद्र कापरेकर; 17 January 1905 – 4 July 1986) was an Indian recreational mathematician who described several classes of natural numbers including the Kaprekar, Harshad and self numbers and discovered Kaprekar's constant, named after him. Despite having no formal postgraduate training and working as a schoolteacher, he published extensively and became well known in recreational mathematics circles. Working largely alone, Kaprekar discovered a number of results in number theory and described various properties of numbers. In 1955, Kaprekar discovered an interesting property of the number 6174, which was subsequently named the Kaprekar constant. Today his name is well-known and many other mathematicians have pursued the study of the properties he discovered.
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