Number Facts Generator
Discover interesting mathematical facts about any number. Trivia, primes, divisors and more.
About this calculator
Enter any number and see mathematical facts: whether it is prime, even or odd, its factors, square, cube, binary form and more.
A quick way to explore numbers.
How to use it
- Enter a number.
- Press Get Facts.
- Read the properties.
Properties explained
A prime has exactly two divisors, 1 and itself. A perfect number equals the sum of its proper divisors (6 = 1+2+3; 28 = 1+2+4+7+14). A square is n × n. Binary is base 2. A number is divisible by 3 if its digit sum is, and by 9 likewise.
Worked example
Number 28
| Factors | 1, 2, 4, 7, 14, 28 |
| Perfect? | Yes (1+2+4+7+14 = 28) |
| Binary | 11100 |
Tips and common mistakes
- Check divisibility rules to factor faster.
- Primes below 30: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29.
- Squares end in 0, 1, 4, 5, 6 or 9.
- Use binary for computing.
- Try numbers like 1729.
Frequently asked questions
What is a prime number?
A number greater than 1 with only two divisors.
What is a perfect number?
One equal to the sum of its proper divisors.
Is 1 prime?
No.
What is 28 in binary?
11100.
What's special about 1729?
The smallest number that's the sum of two cubes in two ways.
Is it free?
Yes.