Number reference
0 explained.
0: zero, zero; factors, prime factorization, roots, binary, hexadecimal, and digit properties.
Identity and representations
- Written form
- zero
- Classification
- zero
- Factors
- Prime factorization
- 0
- Square root
- 0
- Cube root
- 0
- Binary
- 0
- Octal
- 0
- Hexadecimal
- 0
- Roman numeral
- —
- Digit sum
- 0
- Digital root
- 0
0 in everyday use
Zero is the additive identity: adding it to any number leaves that number unchanged. It is neither prime nor composite, and as a placeholder digit it is what makes positional notation work — without it, 105 and 15 could not be told apart.
Nearby numbers
How to read this page
Zero behaves differently from every other entry in this set: it has no prime factorisation, every integer divides it, and dividing by it is undefined. The base representations still apply, which is why it is kept in the reference.
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