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. == Education and work == Kaprekar received his secondary school education in Thane and studied at Fergusson College in Pune. In 1927, he won the Wrangler R. P. Paranjpye Mathematical Prize for an original piece of work in mathematics. He attended the University of Mumbai, receiving his bachelor's degree in 1929. He was a schoolteacher at the government junior school in Devlali, Maharashtra, India for his entire career (1930-1962). Cycling from place to place, he also tutored private students with unconventional methods, cheerfully sitting by a river and "thinking of theorems". He published extensively, writing about such topics as recurring decimals, magic squares, and integers with special properties. == Discoveries == Working largely alone, Kaprekar discovered a number of results in number theory and described various properties of numbers. In addition to the Kaprekar's constant and the Kaprekar numbers which were named after him, he also described self numbers or Devlali numbers, the harshad numbers and Demlo numbers.
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