Ivan Niven
Ivan Morton Niven (25 October 1915 - 9 May 1999) was a Canadian mathematician who helped proved the conjectured answers for Waring’s problem. In 1997 he presented a paper on integers that are divisible by their digit sum, but the name given them by Shri Dattathreya Ramachandra Kaprekar, “Harshad numbers,” has stuck more than “Niven numbers.” Asteroid 12513 bears Niven’s name.