The number 82640
82640 is a composite number with 20 divisors. Its prime factorisation is × 5 × 1033. Divisors (20): 1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 1033, 2066, 4132, 5165, 8264, 10330 … 82640.
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How to work it out
- 1
What is special about 82640: a Harshad number: divisible by its digit sum 20.
- 2
82640 is composite. Its prime factorisation is
- 3
The divisors add up to 192324; without 82640 itself that is 109684, so 82640 is abundant (109684 is more than 82640). Euler's totient φ(82640) = 33024 numbers up to 82640 share no factor with it.
- 4
The digits of 82640 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 58 steps to reach 1.
LaTeX source of the formulas on this page
\[ 82640 = 2^{4} \times 5 \times 1033 \]82640 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 192324 |
| Euler totient φ(n) | 33024 |
| Square | 6829369600 |
| Cube | 564379103744000 |
| Square root | 287.471738 (= 4√5165) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 58 |
| Scientific notation | 8.264 × |
82640 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand six hundred and forty |
| Binary (base 2) | 10100001011010000 |
| Octal (base 8) | 241320 |
| Hexadecimal (base 16) | 142D0 |
| Base 3 | 11012100202 |
| As time | 82640 seconds = 22 h 57 min 20 s |
Is 82640 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (82640 ÷ 2 = 41320) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (82640 ÷ 4 = 20660) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (82640 ÷ 5 = 16528) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 (82640 ÷ 8 = 10330) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (82640 ÷ 10 = 8264) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 82640 a prime number?
No. 82640 = × 5 × 1033, so it is divisible by 2.
What are the factors of 82640?
1, 2, 4, 5, 8, 10, 16, 20, 40, 80, 1033, 2066, 4132, 5165, 8264, 10330, 16528, 20660, 41320, 82640.
What is 82640 in binary?
10100001011010000 (hexadecimal 142D0, octal 241320).
What is the square root of 82640?
About 287.4717, exactly 4√5165.
Is 82640 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 82640?
82640 is a Harshad number: divisible by its digit sum 20.