I am an even two-digit number. Both of my digits are prime numbers, and my digits add up to a square number. What number am I?
72
The digits of 72 are 7 and 2, both of which are prime numbers. 72 is even, and the sum of its digits is 7 + 2 = 9, which is a square number (3^2).
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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