495
495 is Kaprekar's constant for three-digit numbers.
- Odd
- Composite
Where 495 fits
Why 495 is special
Take any three-digit number with at least two different digits, arrange the digits into the largest and smallest numbers possible, subtract, and repeat. Every starting point reaches 495 within six steps and stays there. The four-digit version of the same process converges on 6174.
Factors & digit properties
- Divisors (12)
- 1, 3, 5, 9, 11, 15, 33, 45, 55, 99, 165, 495
- Prime factorisation
- 3^2 × 5 × 11
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 495
- Binary
- 111101111
- Octal
- 757
- Hexadecimal
- 1ef
- Roman numeral
- CDXCV
- Scientific notation
- 4.950 × 10^2
Other mathematical patterns
- Deficient number
- Lucky number (mathematical sieve)
Related numbers & connections
Kaprekar's constants for three and four digits. The same rearrange-and-subtract routine converges on 495 from any three-digit start and on 6,174 from any four-digit one.
View 6174 →Shares a distinctive class
- is associated with6174
why?
Strength 0.50, confidence "high".
Mathematics
Arrange any three-digit number's digits into the largest and smallest values possible, subtract, repeat. Every starting point with at least two distinct digits reaches 495 within six iterations and then stays. The four-digit version of the same routine settles on 6,174.
DocumentedMathematics
Common questions
Is 495 a prime number?
No, 495 is not prime.
What are the factors of 495?
The factors of 495 are 1, 3, 5, 9, 11, 15, 33, 45, 55, 99, 165, 495.
What is 495 in Roman numerals?
495 in Roman numerals is CDXCV.
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