Prime Number Checker
One entry per line - check primality, list primes in a range, or find the Nth prime
Mode:
Max results:
Separator:
Calculation Result
Download CSV
| No. | Value | Result | Detail |
|---|
Introduction to the tool and how to use it
Test primality, generate prime lists and look up the Nth prime - three common jobs in one box, one entry per line.
How to use:
1. Pick a mode:
- Check: one integer per line, e.g.
- List: one range per line, e.g.
- Nth prime: one index per line, e.g.
2. Hit Run to get the verdict, the number of primes or the Nth prime;
3. Copy the result or export it as CSV.
Composites come with their smallest prime factor (360 = 2 x 180) while primes are marked as yes. Big integers are tested with BigInt plus Miller-Rabin (deterministic below 2^64), and ranges use a sieve of Eratosthenes that answers instantly below 5,000,000.
How to use:
1. Pick a mode:
- Check: one integer per line, e.g.
97;- List: one range per line, e.g.
100,200;- Nth prime: one index per line, e.g.
1000;2. Hit Run to get the verdict, the number of primes or the Nth prime;
3. Copy the result or export it as CSV.
Composites come with their smallest prime factor (360 = 2 x 180) while primes are marked as yes. Big integers are tested with BigInt plus Miller-Rabin (deterministic below 2^64), and ranges use a sieve of Eratosthenes that answers instantly below 5,000,000.
Prime test
Is 101 a prime number?
101 is a prime number, divisible only by 1 and itself.
- Prime?Yes
- Divisors2
- Factors1, 101
- Previous prime97
- Next prime103
Divisor list
| # | Divisor |
|---|---|
| 1 | 1 |
| 2 | 101 |
- Large numbers are decided with Miller-Rabin (12 bases), which is deterministic below 2^64.
Common inputs
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