I am a two-digit prime number. Reverse my digits and you get a perfect square. Add my digits together and you get another prime number. What number am I?
61
61 is a prime number. Reversing its digits yields 16, which is 4 squared. Adding its digits (6 + 1) gives 7, which is also a prime number.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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