I am a single-digit integer strictly greater than 1. When you raise me to the third power, the product terminates in my digit. When you square me, the sum of the digits in the result equals my value. What number am I?
9
9 cubed is 729 (ends in 9), and 9 squared is 81 (digits sum to 8 + 1 = 9).
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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