PRMO 2019 question 6

Let abc be a three digit number with nonzero digits such that a^2 + b^2 = c^2.
What is the largest possible prime factor of abc?

Solution:
Only single digit Pythagorean triplet is 3,4,5 so the number could be 345 or 435.
345 = 3 x 5 x 23
435 = 3 x 5 x 29

Answer: 29

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