The number 32991
32991 is a composite number with 8 divisors. Its prime factorisation is 3 × 7 × 1571. Divisors (8): 1, 3, 7, 21, 1571, 4713, 10997, 32991.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 32991: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
32991 is composite. Its prime factorisation is
- 3
The divisors add up to 50304; without 32991 itself that is 17313, so 32991 is deficient (17313 is less than 32991). Euler's totient φ(32991) = 18840 numbers up to 32991 share no factor with it.
- 4
The digits of 32991 add up to 24, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 147 steps to reach 1.
LaTeX source of the formulas on this page
\[ 32991 = 3 \times 7 \times 1571 \]
32991 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 50304 |
| Euler totient φ(n) | 18840 |
| Square | 1088406081 |
| Cube | 35907605018271 |
| Square root | 181.634248 |
| Digit sum / digital root | 24 / 6 |
| Collatz steps to 1 | 147 |
| Scientific notation | 3.2991 × |
32991 in other forms
| Form | Value |
|---|---|
| In words | thirty-two thousand nine hundred and ninety-one |
| Binary (base 2) | 1000000011011111 |
| Octal (base 8) | 100337 |
| Hexadecimal (base 16) | 80DF |
| Base 3 | 1200020220 |
| As time | 32991 seconds = 9 h 9 min 51 s |
Is 32991 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 (32991 ÷ 3 = 10997) | 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 | Yes (32991 ÷ 7 = 4713) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 2) | 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 32991 a prime number?
No. 32991 = 3 × 7 × 1571, so it is divisible by 3.
What are the factors of 32991?
1, 3, 7, 21, 1571, 4713, 10997, 32991.
What is 32991 in binary?
1000000011011111 (hexadecimal 80DF, octal 100337).
What is the square root of 32991?
About 181.6342.
Is 32991 divisible by 3?
Yes. Its digits add up to 24, a multiple of 3.
What is special about the number 32991?
32991 is a happy number: repeatedly adding the squares of its digits reaches 1.