273
273 is the rounded number of Celsius degrees between absolute zero and the freezing point of water. Absolute zero is exactly −273.15 °C.
- Odd
- Composite
Where 273 fits
Why 273 is special
273 is the everyday shorthand for the gap between the two zeroes of temperature: the Celsius scale starts at water's freezing point, the Kelvin scale starts at absolute zero, and they are offset by exactly 273.15 degrees. The rounded 273 is what most conversions use in practice, but the .15 is not a measurement uncertainty — both scales are defined so that the offset is exact.
273 is part of
Factors & digit properties
- Divisors (8)
- 1, 3, 7, 13, 21, 39, 91, 273
- Prime factorisation
- 3 × 7 × 13
- Digit sum
- 12
- Digital root
- 3
Representations
- Decimal
- 273
- Binary
- 100010001
- Octal
- 421
- Hexadecimal
- 111
- Roman numeral
- CCLXXIII
- Scientific notation
- 2.730 × 10^2
Other mathematical patterns
- Deficient number
- Lucky number (mathematical sieve)
Related numbers & connections
Zero degrees Celsius is a convenience and absolute zero is a physical limit, sitting 273.15 apart on the same scale.
View 0 →Other connections
- is associated with0
why?
Strength 0.50, confidence "high".
- is associated withTemperature scales
why?
Strength 0.50, confidence "high".
Science
The Celsius and Kelvin scales use degrees of identical size but different zero points, offset by exactly 273.15: water freezes at 0 °C, which is 273.15 K. Converting between them is therefore addition alone, with no scaling.
DocumentedScienceAbsolute zero — the lower limit of the thermodynamic temperature scale — is exactly −273.15 °C, or 0 kelvin. 273 is the rounded figure used in everyday references; the .15 is exact by definition, not a measurement uncertainty.
DocumentedScience
Common questions
Is 273 a prime number?
No, 273 is not prime.
What are the factors of 273?
The factors of 273 are 1, 3, 7, 13, 21, 39, 91, 273.
What is 273 in Roman numerals?
273 in Roman numerals is CCLXXIII.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 3 August 2026