The number 40491
40491 is a composite number with 12 divisors. Its prime factorisation is × 11 × 409. Divisors (12): 1, 3, 9, 11, 33, 99, 409, 1227, 3681, 4499, 13497, 40491.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
40491 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
40491 is composite. Its prime factorisation is
- 3
The divisors add up to 63960; without 40491 itself that is 23469, so 40491 is deficient (23469 is less than 40491). Euler's totient φ(40491) = 24480 numbers up to 40491 share no factor with it.
- 4
The digits of 40491 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 75 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40491 = 3^{2} \times 11 \times 409 \]40491 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 63960 |
| Euler totient φ(n) | 24480 |
| Square | 1639521081 |
| Cube | 66385848090771 |
| Square root | 201.223756 (= 3√4499) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 75 |
| Scientific notation | 4.0491 × |
40491 in other forms
| Form | Value |
|---|---|
| In words | forty thousand four hundred and ninety-one |
| Binary (base 2) | 1001111000101011 |
| Octal (base 8) | 117053 |
| Hexadecimal (base 16) | 9E2B |
| Base 3 | 2001112200 |
| As time | 40491 seconds = 11 h 14 min 51 s |
Is 40491 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (40491 ÷ 3 = 13497) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (40491 ÷ 9 = 4499) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (40491 ÷ 11 = 3681) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 40491 a prime number?
No. 40491 = × 11 × 409, so it is divisible by 3.
What are the factors of 40491?
1, 3, 9, 11, 33, 99, 409, 1227, 3681, 4499, 13497, 40491.
What is 40491 in binary?
1001111000101011 (hexadecimal 9E2B, octal 117053).
What is the square root of 40491?
About 201.2238, exactly 3√4499.
Is 40491 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 40491?
It is a composite number with 12 divisors.