The number 20722
20722 is a composite number with 8 divisors. Its prime factorisation is 2 × 13 × 797. Divisors (8): 1, 2, 13, 26, 797, 1594, 10361, 20722.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 20722: a Harshad number: divisible by its digit sum 13.
- 2
20722 is composite. Its prime factorisation is
- 3
The divisors add up to 33516; without 20722 itself that is 12794, so 20722 is deficient (12794 is less than 20722). Euler's totient φ(20722) = 9552 numbers up to 20722 share no factor with it.
- 4
The digits of 20722 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 118 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20722 = 2 \times 13 \times 797 \]
20722 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 33516 |
| Euler totient φ(n) | 9552 |
| Square | 429401284 |
| Cube | 8898053407048 |
| Square root | 143.951381 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 118 |
| Scientific notation | 2.0722 × |
20722 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand seven hundred and twenty-two |
| Binary (base 2) | 101000011110010 |
| Octal (base 8) | 50362 |
| Hexadecimal (base 16) | 50F2 |
| Base 3 | 1001102111 |
| As time | 20722 seconds = 5 h 45 min 22 s |
Is 20722 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20722 ÷ 2 = 10361) | 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 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20722 a prime number?
No. 20722 = 2 × 13 × 797, so it is divisible by 2.
What are the factors of 20722?
1, 2, 13, 26, 797, 1594, 10361, 20722.
What is 20722 in binary?
101000011110010 (hexadecimal 50F2, octal 50362).
What is the square root of 20722?
About 143.9514.
Is 20722 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 20722?
20722 is a Harshad number: divisible by its digit sum 13.