The number 8091
8091 is a composite number with 12 divisors. Its prime factorisation is × 29 × 31. Divisors (12): 1, 3, 9, 29, 31, 87, 93, 261, 279, 899, 2697, 8091.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
8091 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
8091 is composite. Its prime factorisation is
- 3
The divisors add up to 12480; without 8091 itself that is 4389, so 8091 is deficient (4389 is less than 8091). Euler's totient φ(8091) = 5040 numbers up to 8091 share no factor with it.
- 4
The digits of 8091 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 189 steps to reach 1.
LaTeX source of the formulas on this page
\[ 8091 = 3^{2} \times 29 \times 31 \]8091 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 12480 |
| Euler totient φ(n) | 5040 |
| Square | 65464281 |
| Cube | 529671497571 |
| Square root | 89.949986 (= 3√899) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 189 |
| Scientific notation | 8.091 × |
8091 in other forms
| Form | Value |
|---|---|
| In words | eight thousand and ninety-one |
| Binary (base 2) | 1111110011011 |
| Octal (base 8) | 17633 |
| Hexadecimal (base 16) | 1F9B |
| Base 3 | 102002200 |
| As time | 8091 seconds = 2 h 14 min 51 s |
Is 8091 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 (8091 ÷ 3 = 2697) | 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 6) | 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 (8091 ÷ 9 = 899) | 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 | No (remainder 6) | 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 8091 a prime number?
No. 8091 = × 29 × 31, so it is divisible by 3.
What are the factors of 8091?
1, 3, 9, 29, 31, 87, 93, 261, 279, 899, 2697, 8091.
What is 8091 in binary?
1111110011011 (hexadecimal 1F9B, octal 17633).
What is the square root of 8091?
About 89.9500, exactly 3√899.
Is 8091 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 8091?
It is a composite number with 12 divisors.