Prime Number Checker and Calculator
Check if a number is prime, find the next or previous prime, or list all primes up to any number. Simple, fast, and great for students or math lovers.
Result
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How to Use the Prime Number Calculator
- Enter any number to check if it’s prime.
- Use the "List" mode to get all primes up to a specific value.
- View detailed steps by enabling the explanation option.
- Tap “Next” or "Previous" to explore nearby primes.
What is prime number?
A prime number is a number greater than 1 that has no positive divisors other than 1 and itself. Examples: 2, 3, 5, 7, 11…
How Do You Check If a Number Is Prime?
Mathematically, a number n is prime if it is not divisible by any number from 2 up to √n. Our calculator uses an efficient algorithm for this.
Real-World Use Cases
- School assignments & homework
- Competitive exam prep (like SAT, GRE)
- Coding interviews or algorithm challenges
- Number theory research
Frequently Asked Questions
What is a prime number?
A number greater than 1 that has no divisors other than 1 and itself. For example, 2, 3, 5, 7 are all prime numbers.
What is the smallest prime number?
2 is the smallest and only even prime number.
How do I find the next or previous prime?
Enter a number, then click the “Next” or “Previous” buttons to find nearby primes.
Can 1 be a prime number?
No. 1 is not a prime because it only has one factor — itself.