The number 82987
82987 is a composite number with 4 divisors. Its prime factorisation is 31 × 2677. Divisors (4): 1, 31, 2677, 82987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 82987: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 31 × 2677, the product of two primes.
- 2
82987 is composite. Its prime factorisation is
- 3
The divisors add up to 85696; without 82987 itself that is 2709, so 82987 is deficient (2709 is less than 82987). Euler's totient φ(82987) = 80280 numbers up to 82987 share no factor with it.
- 4
The digits of 82987 add up to 34, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 82987 = 31 \times 2677 \]
82987 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 85696 |
| Euler totient φ(n) | 80280 |
| Square | 6886842169 |
| Cube | 571518371078803 |
| Square root | 288.074643 |
| Digit sum / digital root | 34 / 7 |
| Collatz steps to 1 | 89 |
| Scientific notation | 8.2987 × |
82987 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand nine hundred and eighty-seven |
| Binary (base 2) | 10100010000101011 |
| Octal (base 8) | 242053 |
| Hexadecimal (base 16) | 1442B |
| Base 3 | 11012211121 |
| As time | 82987 seconds = 23 h 3 min 7 s |
Is 82987 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 | No (remainder 1) | 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 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 82987 a prime number?
No. 82987 = 31 × 2677, so it is divisible by 31.
What are the factors of 82987?
1, 31, 2677, 82987.
What is 82987 in binary?
10100010000101011 (hexadecimal 1442B, octal 242053).
What is the square root of 82987?
About 288.0746.
Is 82987 divisible by 3?
No. Its digits add up to 34, which is not a multiple of 3.
What is special about the number 82987?
82987 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 31 × 2677, the product of two primes.