The number 20824
20824 is a composite number with 16 divisors. Its prime factorisation is × 19 × 137. Divisors (16): 1, 2, 4, 8, 19, 38, 76, 137, 152, 274, 548, 1096, 2603, 5206, 10412, 20824.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
20824 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
20824 is composite. Its prime factorisation is
- 3
The divisors add up to 41400; without 20824 itself that is 20576, so 20824 is deficient (20576 is less than 20824). Euler's totient φ(20824) = 9792 numbers up to 20824 share no factor with it.
- 4
The digits of 20824 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 105 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20824 = 2^{3} \times 19 \times 137 \]20824 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 41400 |
| Euler totient φ(n) | 9792 |
| Square | 433638976 |
| Cube | 9030098036224 |
| Square root | 144.305232 (= 2√5206) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 105 |
| Scientific notation | 2.0824 × |
20824 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand eight hundred and twenty-four |
| Binary (base 2) | 101000101011000 |
| Octal (base 8) | 50530 |
| Hexadecimal (base 16) | 5158 |
| Base 3 | 1001120021 |
| As time | 20824 seconds = 5 h 47 min 4 s |
Is 20824 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20824 ÷ 2 = 10412) | 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 (20824 ÷ 4 = 5206) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 6) | 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 (20824 ÷ 8 = 2603) | 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 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | 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 20824 a prime number?
No. 20824 = × 19 × 137, so it is divisible by 2.
What are the factors of 20824?
1, 2, 4, 8, 19, 38, 76, 137, 152, 274, 548, 1096, 2603, 5206, 10412, 20824.
What is 20824 in binary?
101000101011000 (hexadecimal 5158, octal 50530).
What is the square root of 20824?
About 144.3052, exactly 2√5206.
Is 20824 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 20824?
It is a composite number with 16 divisors.