The number 20997
20997 is a composite number with 6 divisors. Its prime factorisation is × 2333. Divisors (6): 1, 3, 9, 2333, 6999, 20997.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
20997 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
20997 is composite. Its prime factorisation is
- 3
The divisors add up to 30342; without 20997 itself that is 9345, so 20997 is deficient (9345 is less than 20997). Euler's totient φ(20997) = 13992 numbers up to 20997 share no factor with it.
- 4
The digits of 20997 add up to 27, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 131 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20997 = 3^{2} \times 2333 \]20997 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 30342 |
| Euler totient φ(n) | 13992 |
| Square | 440874009 |
| Cube | 9257031566973 |
| Square root | 144.903416 (= 3√2333) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 131 |
| Scientific notation | 2.0997 × |
20997 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand nine hundred and ninety-seven |
| Binary (base 2) | 101001000000101 |
| Octal (base 8) | 51005 |
| Hexadecimal (base 16) | 5205 |
| Base 3 | 1001210200 |
| As time | 20997 seconds = 5 h 49 min 57 s |
Is 20997 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 (20997 ÷ 3 = 6999) | 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 2) | 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 | Yes (20997 ÷ 9 = 2333) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | 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 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20997 a prime number?
No. 20997 = × 2333, so it is divisible by 3.
What are the factors of 20997?
1, 3, 9, 2333, 6999, 20997.
What is 20997 in binary?
101001000000101 (hexadecimal 5205, octal 51005).
What is the square root of 20997?
About 144.9034, exactly 3√2333.
Is 20997 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 20997?
It is a composite number with 6 divisors.