Problems & Puzzles: Puzzles

Puzzle 733. Integers equal to the sum of the squares of their prime divisors.

My friend Frank Rubin asks in one of his interesting pages:

"Which whole numbers are equal to the sum of the squares of their prime divisors? For example, 16=2×2×2×2=2²+2²+2²+2² and 27=3×3×3=3²+3²+3²."

Q. Can you find a third solution or prove that no more solutions exist?


Giorgos Kalogeropoulos remind me on Jan 21, 2024, that he solved this puzzle in Puzzle 625

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