Number Facts and Properties
See the key properties of any number — parity, primality, factors, digit sum and more.
About the Number Facts and Properties
Enter any whole number and the AlarmDaddy Number Facts calculator lays out everything interesting about it at a glance: whether it is even or odd, positive or negative, prime or composite, how many divisors it has and their sum, its digit sum and digital root, whether it is a perfect square or cube, and its binary, hexadecimal and Roman-numeral forms.
It is a handy reference for maths homework, number theory practice, and quick sanity checks. Everything is computed in your browser, instantly, for numbers up to a trillion.
How to use this calculator
- 1Enter a whole number.
- 2Read its parity, primality and sign.
- 3See divisor count and sum, digit sum, digital root, and binary/hex/Roman forms.
The formula
Even/odd comes from the remainder when dividing by 2. Primality is tested by trial division up to the square root. The digit sum adds the digits once; the digital root repeats that until a single digit remains. Base forms use standard base conversion.