The number 20706
20706 is a triangular number: 1 + 2 + … + 203 = 20706. Its prime factorisation is 2 × 3 × 7 × 17 × 29. Divisors (32): 1, 2, 3, 6, 7, 14, 17, 21, 29, 34, 42, 51, 58, 87, 102, 119 … 20706.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20706: a triangular number: 1 + 2 + … + 203 = 20706.
- 2
20706 is composite. Its prime factorisation is
- 3
The divisors add up to 51840; without 20706 itself that is 31134, so 20706 is abundant (31134 is more than 20706). Euler's totient φ(20706) = 5376 numbers up to 20706 share no factor with it.
- 4
The digits of 20706 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 105 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20706 = 2 \times 3 \times 7 \times 17 \times 29 \]
20706 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 51840 |
| Euler totient φ(n) | 5376 |
| Square | 428738436 |
| Cube | 8877458055816 |
| Square root | 143.895796 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 105 |
| Scientific notation | 2.0706 × |
20706 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand seven hundred and six |
| Binary (base 2) | 101000011100010 |
| Octal (base 8) | 50342 |
| Hexadecimal (base 16) | 50E2 |
| Base 3 | 1001101220 |
| As time | 20706 seconds = 5 h 45 min 6 s |
Is 20706 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20706 ÷ 2 = 10353) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20706 ÷ 3 = 6902) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (20706 ÷ 6 = 3451) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (20706 ÷ 7 = 2958) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 6) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20706 a prime number?
No. 20706 = 2 × 3 × 7 × 17 × 29, so it is divisible by 2.
What are the factors of 20706?
1, 2, 3, 6, 7, 14, 17, 21, 29, 34, 42, 51, 58, 87, 102, 119, 174, 203, 238, 357, 406, 493, 609, 714, 986, 1218, 1479, 2958, 3451, 6902, 10353, 20706.
What is 20706 in binary?
101000011100010 (hexadecimal 50E2, octal 50342).
What is the square root of 20706?
About 143.8958.
Is 20706 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 20706?
20706 is a triangular number: 1 + 2 + … + 203 = 20706.