40 is an even composite number. It is composed of two distinct prime numbers multiplied together. It has a total of eight divisors.
Prime factorization of 40:
23 × 5
(2 × 2 × 2 × 5)
23 × 5(2 × 2 × 2 × 5)
See below for interesting mathematical facts about the number 40 from the Numbermatics database.
Names of 40
- Cardinal: 40 can be written as Forty.
- Scientific notation: 4 × 101
Factors of 40
- Number of distinct prime factors ω(n): 2
- Total number of prime factors Ω(n): 4
- Sum of prime factors: 7
Divisors of 40
- Number of divisors d(n): 8
- Complete list of divisors:
- Sum of all divisors σ(n): 90
- Sum of proper divisors (its aliquot sum) s(n): 50
- 40 is an abundant number, because the sum of its proper divisors (50) is greater than itself. Its abundance is 10
Bases of 40
- Binary: 101000 2
- Hexadecimal: 0x28
- Base-36: 14
Squares and roots of 40
- 40 squared (402) is 1600
- 40 cubed (403) is 64000
square rootof 40 is 6.3245553203
cube rootof 40 is 3.4199518931
Scales and comparisonsHow big is 40?
To count from 1 to 40 would take you about twenty 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 40 cubic inches would be around 0.3 feet tall.
Recreational maths with 40
- 40 backwards is 04
- 40 is a
- The number of decimal digits it has is: 2
- The sum of 40's digits is 4
- More coming soon!
The information we have on file for 40 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!