The number 81322
81322 is a composite number with 8 divisors. Its prime factorisation is 2 × 73 × 557. Divisors (8): 1, 2, 73, 146, 557, 1114, 40661, 81322.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 81322: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
81322 is composite. Its prime factorisation is
- 3
The divisors add up to 123876; without 81322 itself that is 42554, so 81322 is deficient (42554 is less than 81322). Euler's totient φ(81322) = 40032 numbers up to 81322 share no factor with it.
- 4
The digits of 81322 add up to 16, 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
\[ 81322 = 2 \times 73 \times 557 \]
81322 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 123876 |
| Euler totient φ(n) | 40032 |
| Square | 6613267684 |
| Cube | 537804154598248 |
| Square root | 285.170125 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 37 |
| Scientific notation | 8.1322 × |
81322 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand three hundred and twenty-two |
| Binary (base 2) | 10011110110101010 |
| Octal (base 8) | 236652 |
| Hexadecimal (base 16) | 13DAA |
| Base 3 | 11010112221 |
| As time | 81322 seconds = 22 h 35 min 22 s |
Is 81322 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81322 ÷ 2 = 40661) | 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 | No (remainder 2) | 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 | No (remainder 4) | 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 2) | 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 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81322 a prime number?
No. 81322 = 2 × 73 × 557, so it is divisible by 2.
What are the factors of 81322?
1, 2, 73, 146, 557, 1114, 40661, 81322.
What is 81322 in binary?
10011110110101010 (hexadecimal 13DAA, octal 236652).
What is the square root of 81322?
About 285.1701.
Is 81322 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 81322?
81322 is a happy number: repeatedly adding the squares of its digits reaches 1.