Prime Number Checker

Check prime numbers instantly with nearest-prime insights and factor hints for faster math learning.

Enter a positive integer greater than 1.
Choose whether to show extended prime details.
Click "Check Prime" or use "Previous/Next Prime" buttons to explore nearby primes.

Input: 21

Output: Not prime, smallest divisor 3, and nearby primes 19 and 23

What is a prime number?A prime number is divisible only by 1 and itself, such as 2, 3, 5, and 7.

Can this tool help with number theory practice?Yes. It provides quick checks plus nearby prime references for learning patterns.