MediumScience
"I am a number with exactly two factors. I am divisible only by one and myself. There are infinitely many of me, but I become rarer as numbers grow larger. What am I?"
Answer
A Prime Number
Explanation
A prime number is divisible only by 1 and itself. There are infinitely many primes (proved by Euclid around 300 BC) but they become increasingly rare as numbers get larger. Prime numbers are the foundation of modern encryption and internet security.
This is a medium riddle in the Science category — Riddles about physics, space, biology and the laws of the universe.
Tags:mathsclassic
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