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Prime Factorizer
Factor big whole numbers into primes, list divisors, check primality, and find GCD and LCM.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Prime Factorizer works
All maths runs in your browser. Exact fractions and big integers are used where rounding would give wrong answers. Uses BigInt, Miller-Rabin primality testing and Pollard rho factoring.
Input: Text. Output: Text.
How to use Prime Factorizer
- Type a number up to 40 digits.
- Read the factors, divisors and nearest primes.
- Add a list for GCD and LCM.
Tips
- Exact fractions are used where rounding would give wrong answers.
- Every tool works offline once the page has loaded.
Prime Factorizer FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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