The number 20829
20829 is a composite number with 8 divisors. Its prime factorisation is 3 × 53 × 131. Divisors (8): 1, 3, 53, 131, 159, 393, 6943, 20829.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
20829 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
20829 is composite. Its prime factorisation is
- 3
The divisors add up to 28512; without 20829 itself that is 7683, so 20829 is deficient (7683 is less than 20829). Euler's totient φ(20829) = 13520 numbers up to 20829 share no factor with it.
- 4
The digits of 20829 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 105 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20829 = 3 \times 53 \times 131 \]
20829 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 28512 |
| Euler totient φ(n) | 13520 |
| Square | 433847241 |
| Cube | 9036604182789 |
| Square root | 144.322555 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 105 |
| Scientific notation | 2.0829 × |
20829 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand eight hundred and twenty-nine |
| Binary (base 2) | 101000101011101 |
| Octal (base 8) | 50535 |
| Hexadecimal (base 16) | 515D |
| Base 3 | 1001120110 |
| As time | 20829 seconds = 5 h 47 min 9 s |
Is 20829 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 (20829 ÷ 3 = 6943) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | 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 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20829 a prime number?
No. 20829 = 3 × 53 × 131, so it is divisible by 3.
What are the factors of 20829?
1, 3, 53, 131, 159, 393, 6943, 20829.
What is 20829 in binary?
101000101011101 (hexadecimal 515D, octal 50535).
What is the square root of 20829?
About 144.3226.
Is 20829 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 20829?
It is a composite number with 8 divisors.