The number 20493
20493 is a composite number with 20 divisors. Its prime factorisation is × 11 × 23. Divisors (20): 1, 3, 9, 11, 23, 27, 33, 69, 81, 99, 207, 253, 297, 621, 759, 891 … 20493.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
20493 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
20493 is composite. Its prime factorisation is
- 3
The divisors add up to 34848; without 20493 itself that is 14355, so 20493 is deficient (14355 is less than 20493). Euler's totient φ(20493) = 11880 numbers up to 20493 share no factor with it.
- 4
The digits of 20493 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 149 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20493 = 3^{4} \times 11 \times 23 \]20493 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 20 |
| Sum of divisors | 34848 |
| Euler totient φ(n) | 11880 |
| Square | 419963049 |
| Cube | 8606302763157 |
| Square root | 143.153763 (= 9√253) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 149 |
| Scientific notation | 2.0493 × |
20493 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand four hundred and ninety-three |
| Binary (base 2) | 101000000001101 |
| Octal (base 8) | 50015 |
| Hexadecimal (base 16) | 500D |
| Base 3 | 1001010000 |
| As time | 20493 seconds = 5 h 41 min 33 s |
Is 20493 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 (20493 ÷ 3 = 6831) | 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 3) | 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 (20493 ÷ 9 = 2277) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (20493 ÷ 11 = 1863) | 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 20493 a prime number?
No. 20493 = × 11 × 23, so it is divisible by 3.
What are the factors of 20493?
1, 3, 9, 11, 23, 27, 33, 69, 81, 99, 207, 253, 297, 621, 759, 891, 1863, 2277, 6831, 20493.
What is 20493 in binary?
101000000001101 (hexadecimal 500D, octal 50015).
What is the square root of 20493?
About 143.1538, exactly 9√253.
Is 20493 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 20493?
It is a composite number with 20 divisors.