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## 'Seven Up' printed from http://nrich.maths.org/

The number 27 is special because it is three times the sum of
its digits

27 = 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)?