I am an even number strictly between 20 and 30. The sum of my digits is a perfect square. What number am I?
22
The even numbers strictly between 20 and 30 are 22, 24, 26, and 28. Their digit sums are 4, 6, 8, and 10 respectively. Only 4 is a perfect square (2²), so the number is 22.
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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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