The number 82131
82131 is a composite number with 8 divisors. Its prime factorisation is 3 × 7 × 3911. Divisors (8): 1, 3, 7, 21, 3911, 11733, 27377, 82131.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 82131: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
82131 is composite. Its prime factorisation is
- 3
The divisors add up to 125184; without 82131 itself that is 43053, so 82131 is deficient (43053 is less than 82131). Euler's totient φ(82131) = 46920 numbers up to 82131 share no factor with it.
- 4
The digits of 82131 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 151 steps to reach 1.
LaTeX source of the formulas on this page
\[ 82131 = 3 \times 7 \times 3911 \]
82131 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 125184 |
| Euler totient φ(n) | 46920 |
| Square | 6745501161 |
| Cube | 554014755854091 |
| Square root | 286.585066 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 151 |
| Scientific notation | 8.2131 × |
82131 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand one hundred and thirty-one |
| Binary (base 2) | 10100000011010011 |
| Octal (base 8) | 240323 |
| Hexadecimal (base 16) | 140D3 |
| Base 3 | 11011122220 |
| As time | 82131 seconds = 22 h 48 min 51 s |
Is 82131 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 (82131 ÷ 3 = 27377) | 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 (82131 ÷ 7 = 11733) | 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 3) | 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 5) | 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 82131 a prime number?
No. 82131 = 3 × 7 × 3911, so it is divisible by 3.
What are the factors of 82131?
1, 3, 7, 21, 3911, 11733, 27377, 82131.
What is 82131 in binary?
10100000011010011 (hexadecimal 140D3, octal 240323).
What is the square root of 82131?
About 286.5851.
Is 82131 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 82131?
82131 is a happy number: repeatedly adding the squares of its digits reaches 1.