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The number 27 is special because it is three times the sum of its digits27 = 3 (2 + 7).
Find some two digit numbers that are SEVEN times the sum of their digits (seven-up numbers)?
Are there any three digit 'seven-up' numbers. Is it possible to find a number K such that there is a three digit number that is K times the sum of its digits (a K-up number)?