13 is a prime number. Like all primes (except two), it is an odd number.
Prime factorization of 13:
See below for interesting mathematical facts about the number 13 from the Numbermatics database.
Names of 13
- Cardinal: 13 can be written as Thirteen.
- Scientific notation: 1.3 × 101
Factors of 13
- Number of distinct prime factors ω(n): 1
- Total number of prime factors Ω(n): 1
- Sum of prime factors: 13
Divisors of 13
- Number of divisors d(n): 2
- Complete list of divisors:
- Sum of all divisors σ(n): 14
- Sum of proper divisors (its aliquot sum) s(n): 1
- 13 is a deficient number, because the sum of its proper divisors (1) is less than itself. Its deficiency is 12
Bases of 13
- Binary: 1101 2
- Hexadecimal: 0xd
Squares and roots of 13
- 13 squared (132) is 169
- 13 cubed (133) is 2197
square rootof 13 is 3.6055512755
cube rootof 13 is 2.3513346877
Scales and comparisonsHow big is 13?
To count from 1 to 13 would take you about six seconds.
This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000.
Note: we do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!
- A cube with a volume of 13 cubic inches would be around 0.2 feet tall.
Recreational maths with 13
- 13 backwards is 31
- The number of decimal digits it has is: 2
- The sum of 13's digits is 4
- More coming soon!
The information we have on file for 13 includes mathematical data and numerical statistics calculated using standard algorithms and methods. We are adding more all the time. If there are any features you would like to see, please contact us. Information provided for educational use, intellectual curiosity and fun!