540
The interior angles of any pentagon add up to 540 degrees.
- Even
- Composite
Where 540 fits
Why 540 is special
The rule generalises: an n-sided polygon's interior angles total 180 times (n − 2), because any polygon can be cut into that many triangles. 540 is the pentagon's case, and it is why a regular pentagon's corners are 108 degrees rather than a round number.
Factors & digit properties
- Divisors (24)
- 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 27, 30, 36, 45, 54, 60, 90, 108, 135, 180, 270, 540
- Prime factorisation
- 2^2 × 3^3 × 5
- Digit sum
- 9
- Digital root
- 9
Representations
- Decimal
- 540
- Binary
- 1000011100
- Octal
- 1034
- Hexadecimal
- 21c
- Roman numeral
- DXL
- Scientific notation
- 5.400 × 10^2
Other mathematical patterns
- Abundant number
- Harshad (Niven) number
Related numbers & connections
A pentagon's interior angles total 540 degrees because it divides into three triangles. The rule is 180 times two fewer than the number of sides, for any polygon.
View 180 →Mathematically related
- has multiple180
why?
Strength 0.50, confidence "high".
Mathematics
Any polygon's interior angles total 180 times two fewer than its number of sides, because it can be cut into that many triangles. For a pentagon that is 540, and dividing by five gives the 108-degree corner of the regular case.
DocumentedMathematics
Common questions
Is 540 a prime number?
No, 540 is not prime.
What are the factors of 540?
The factors of 540 are 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 27, 30, 36, 45, 54, 60, 90, 108, 135, 180, 270, 540.
What is 540 in Roman numerals?
540 in Roman numerals is DXL.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 3 August 2026