The number 81088
81088 is a composite number with 28 divisors. Its prime factorisation is × 7 × 181. Divisors (28): 1, 2, 4, 7, 8, 14, 16, 28, 32, 56, 64, 112, 181, 224, 362, 448 … 81088.
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How to work it out
- 1
What is special about 81088: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
81088 is composite. Its prime factorisation is
- 3
The divisors add up to 184912; without 81088 itself that is 103824, so 81088 is abundant (103824 is more than 81088). Euler's totient φ(81088) = 34560 numbers up to 81088 share no factor with it.
- 4
The digits of 81088 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 37 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81088 = 2^{6} \times 7 \times 181 \]81088 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 28 |
| Sum of divisors | 184912 |
| Euler totient φ(n) | 34560 |
| Square | 6575263744 |
| Cube | 533174986473472 |
| Square root | 284.759548 (= 8√1267) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 37 |
| Scientific notation | 8.1088 × |
81088 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand and eighty-eight |
| Binary (base 2) | 10011110011000000 |
| Octal (base 8) | 236300 |
| Hexadecimal (base 16) | 13CC0 |
| Base 3 | 11010020021 |
| As time | 81088 seconds = 22 h 31 min 28 s |
Is 81088 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81088 ÷ 2 = 40544) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (81088 ÷ 4 = 20272) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (81088 ÷ 7 = 11584) | 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 | Yes (81088 ÷ 8 = 10136) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81088 a prime number?
No. 81088 = × 7 × 181, so it is divisible by 2.
What are the factors of 81088?
1, 2, 4, 7, 8, 14, 16, 28, 32, 56, 64, 112, 181, 224, 362, 448, 724, 1267, 1448, 2534, 2896, 5068, 5792, 10136, 11584, 20272, 40544, 81088.
What is 81088 in binary?
10011110011000000 (hexadecimal 13CC0, octal 236300).
What is the square root of 81088?
About 284.7595, exactly 8√1267.
Is 81088 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 81088?
81088 is a happy number: repeatedly adding the squares of its digits reaches 1.