Prime Factorization Calculator - Prime Test, Factors, and Divisor List
Test if a number is prime and get its full prime factorization plus divisor list
How it works
- 1Enter a number
Any positive integer up to 1 trillion.
- 2Read prime test
The tool tells you immediately whether the number is prime or composite.
- 3Read factorization & divisors
Composite numbers show their full prime factorization; numbers up to 1,000,000 also show the complete divisor list.
About Prime Factorization Calculator - Prime Test, Factors, and Divisor List
Free prime factorization calculator. Enter any integer from 1 to 1,000,000,000,000 to check whether it is prime, get its complete prime factorization in exponent form (e.g. 360 = 2³ × 3² × 5), and (for smaller numbers) see the full list of divisors. Uses efficient trial division. Runs entirely in your browser. Prime Factorization Calculator - Prime Test, Factors, and Divisor List on 712 Tools runs entirely inside your browser using modern JavaScript APIs - no server ever sees your data. That means instant results, complete privacy, and no upload limits.
Whether you need to test if a number is prime and get its full prime factorization plus divisor list for a debugging session, a quick sanity check, or a production incident, this tool is free to use as many times as you need. There are no watermarks, no sign-up, and no ads inside the tool itself.
Frequently asked questions
How does the tool factor large numbers?
Trial division up to the square root - fast enough for numbers up to about a trillion in the browser. Very large semiprimes would need more advanced algorithms.
Why is 1 not prime?
By convention. A prime has exactly two distinct positive divisors (1 and itself); 1 only has one.
Is my data uploaded?
No. All calculations run entirely in your browser.
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