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Explorer:
Puzzle of the Day
These puzzles are also printed in Eight days a week, a booklet published by the Association of Teachers of Mathematics.
What is the number if it divides exactly by 13 and when you write its digits in reverse order you make a square number. (You get a square number when you multiply a number by itself - 64 is square because it is 8 times 8)
Answer: 52 or 169
