Factor Generator
Generates a random number between 10 and 500 and lists every one of its positive whole-number factors, found by trial division rather than looked up, for factors-and-multiples practice and as a lead-in to prime factorisation — a prime draw is a valid, if short, result.
What this generator does
Produces a number together with its factors — the whole numbers that divide it exactly. Aimed at factor and multiple work in maths lessons, where the answer is as useful as the question.
How to use this tool
- Press generate for a number and its factors.
Worked examples
- Format
- 76: 1, 2, 4, 19, 38, 76 and 391: 1, 17, 23, 391 — two draws; 391 looks prime and is 17 × 23
Common use cases
- Factors and multiples practice
- Prime-factorisation lead-in exercises
- Quick number-theory reference
How this generator works
A number between 10 and 500 is drawn and every whole number from 1 up to the number itself is tested as a divisor, in order, which is why the factors come out sorted. At this size the full scan is instant; the usual shortcut — testing only up to the square root and pairing each divisor with its partner — matters for large numbers and is not needed here.
Limitations and good to know
- The factors listed are the whole divisors, not the prime factorisation — 12 lists 1, 2, 3, 4, 6 and 12, whose prime form is 2² × 3.
- A prime number has exactly two factors, so a prime draw produces a very short list. That is the correct answer, not a fault.
- Numbers are kept small enough that trial division is instant; factoring large numbers is genuinely hard and is what a good deal of cryptography rests on.
Related generators
- Composite Number GeneratorA random composite (non-prime) number within your chosen range.
- Chinese Remainder Challenge GeneratorSystems of congruences with pairwise coprime moduli and the unique solution below their product, substituted back into every one.
- Prime Factorisation Question GeneratorPrime-factorisation questions built to order, answered in index form, with the factors checked to be prime.