Problem of the Week

A new problem every Monday that challenges participants of all ages to think creatively and apply their math skills. Perfect for a weekly mental challenge.

A Niven number is a positive integer n where the sum of the digits of n divides n. For example, 18 is Niven because the sum of its digits is 9 and 9 divides 18.  Find the number of Niven numbers between 200 and 300 including endpoints (200 and 300).


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