The number 81732
81732 is a composite number with 36 divisors. Its prime factorisation is × 3 × × 139. Divisors (36): 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 49, 84, 98, 139, 147 … 81732.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 81732: a Harshad number: divisible by its digit sum 21.
- 2
81732 is composite. Its prime factorisation is
- 3
The divisors add up to 223440; without 81732 itself that is 141708, so 81732 is abundant (141708 is more than 81732). Euler's totient φ(81732) = 23184 numbers up to 81732 share no factor with it.
- 4
The digits of 81732 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 182 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81732 = 2^{2} \times 3 \times 7^{2} \times 139 \]81732 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 36 |
| Sum of divisors | 223440 |
| Euler totient φ(n) | 23184 |
| Square | 6680119824 |
| Cube | 545979553455168 |
| Square root | 285.888090 (= 14√417) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 182 |
| Scientific notation | 8.1732 × |
81732 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand seven hundred and thirty-two |
| Binary (base 2) | 10011111101000100 |
| Octal (base 8) | 237504 |
| Hexadecimal (base 16) | 13F44 |
| Base 3 | 11011010010 |
| As time | 81732 seconds = 22 h 42 min 12 s |
Is 81732 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81732 ÷ 2 = 40866) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (81732 ÷ 3 = 27244) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (81732 ÷ 4 = 20433) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (81732 ÷ 6 = 13622) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (81732 ÷ 7 = 11676) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | 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 | Yes (81732 ÷ 12 = 6811) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81732 a prime number?
No. 81732 = × 3 × × 139, so it is divisible by 2.
What are the factors of 81732?
1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 49, 84, 98, 139, 147, 196, 278, 294, 417, 556, 588, 834, 973, 1668, 1946, 2919, 3892, 5838, 6811, 11676, 13622, 20433, 27244, 40866, 81732.
What is 81732 in binary?
10011111101000100 (hexadecimal 13F44, octal 237504).
What is the square root of 81732?
About 285.8881, exactly 14√417.
Is 81732 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 81732?
81732 is a Harshad number: divisible by its digit sum 21.