Prime Number Checker

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Understanding Prime Numbers

A prime number is a whole number greater than 1 whose only factors are 1 and itself.

Examples: 2, 3, 5, 7, 11.

Counter Examples: 4 (factors: 1, 2, 4), 9 (factors: 1, 3, 9).

0 and 1 are not prime numbers.
2 is the only even prime number.
Negative numbers are generally not considered prime in standard number theory.