The number 31822
31822 is a composite number with 8 divisors. Its prime factorisation is 2 × 7 × 2273. Divisors (8): 1, 2, 7, 14, 2273, 4546, 15911, 31822.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31822: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
31822 is composite. Its prime factorisation is
- 3
The divisors add up to 54576; without 31822 itself that is 22754, so 31822 is deficient (22754 is less than 31822). Euler's totient φ(31822) = 13632 numbers up to 31822 share no factor with it.
- 4
The digits of 31822 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 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31822 = 2 \times 7 \times 2273 \]
31822 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 54576 |
| Euler totient φ(n) | 13632 |
| Square | 1012639684 |
| Cube | 32224220024248 |
| Square root | 178.387219 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.1822 × |
31822 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand eight hundred and twenty-two |
| Binary (base 2) | 111110001001110 |
| Octal (base 8) | 76116 |
| Hexadecimal (base 16) | 7C4E |
| Base 3 | 1121122121 |
| As time | 31822 seconds = 8 h 50 min 22 s |
Is 31822 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31822 ÷ 2 = 15911) | 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 | Yes (31822 ÷ 7 = 4546) | 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 6) | 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 31822 a prime number?
No. 31822 = 2 × 7 × 2273, so it is divisible by 2.
What are the factors of 31822?
1, 2, 7, 14, 2273, 4546, 15911, 31822.
What is 31822 in binary?
111110001001110 (hexadecimal 7C4E, octal 76116).
What is the square root of 31822?
About 178.3872.
Is 31822 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 31822?
31822 is a happy number: repeatedly adding the squares of its digits reaches 1.