I am a prime number. If you reverse my digits, I am still a prime number, but my sum of digits is 8. What number am I?
17
The digits are 1 and 7, which sum to 8. 17 is prime, and its reverse, 71, is also prime.
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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