I am a prime number. If you reverse my digits, I am still a prime number, but the sum of my new digits is 8. What number am I?
17
Reversing 17 gives 71. Both 17 and 71 are prime numbers, and the digits of 71 add up to 7 + 1 = 8.
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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