The number 82420
82420 is a composite number with 24 divisors. Its prime factorisation is × 5 × 13 × 317. Divisors (24): 1, 2, 4, 5, 10, 13, 20, 26, 52, 65, 130, 260, 317, 634, 1268, 1585 … 82420.
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How to work it out
- 1
82420 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
82420 is composite. Its prime factorisation is
- 3
The divisors add up to 186984; without 82420 itself that is 104564, so 82420 is abundant (104564 is more than 82420). Euler's totient φ(82420) = 30336 numbers up to 82420 share no factor with it.
- 4
The digits of 82420 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 94 steps to reach 1.
LaTeX source of the formulas on this page
\[ 82420 = 2^{2} \times 5 \times 13 \times 317 \]82420 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 186984 |
| Euler totient φ(n) | 30336 |
| Square | 6793056400 |
| Cube | 559883708488000 |
| Square root | 287.088836 (= 2√20605) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 94 |
| Scientific notation | 8.242 × |
82420 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand four hundred and twenty |
| Binary (base 2) | 10100000111110100 |
| Octal (base 8) | 240764 |
| Hexadecimal (base 16) | 141F4 |
| Base 3 | 11012001121 |
| As time | 82420 seconds = 22 h 53 min 40 s |
Is 82420 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (82420 ÷ 2 = 41210) | 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 | Yes (82420 ÷ 4 = 20605) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (82420 ÷ 5 = 16484) | 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 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 4) | 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 | Yes (82420 ÷ 10 = 8242) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 82420 a prime number?
No. 82420 = × 5 × 13 × 317, so it is divisible by 2.
What are the factors of 82420?
1, 2, 4, 5, 10, 13, 20, 26, 52, 65, 130, 260, 317, 634, 1268, 1585, 3170, 4121, 6340, 8242, 16484, 20605, 41210, 82420.
What is 82420 in binary?
10100000111110100 (hexadecimal 141F4, octal 240764).
What is the square root of 82420?
About 287.0888, exactly 2√20605.
Is 82420 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 82420?
It is a composite number with 24 divisors.