I am a prime number. If you reverse my digits, I remain a prime number, but my value increases by 36. What number am I?
37
37 is prime. Reversing its digits gives 73, which is also prime. 73 - 37 = 36.
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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