The number 18443
18443 is the 2113th prime number. Its only divisors are 1 and 18443.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18443: the 2113th prime number.
- 2
18443 is prime, so its only factors are 1 and 18443. It is the 2113th prime; the next prime is 18451 and the one before is 18439.
- 3
The divisors add up to 18444; without 18443 itself that is 1, so 18443 is deficient (1 is less than 18443). Euler's totient φ(18443) = 18442 numbers up to 18443 share no factor with it.
- 4
The digits of 18443 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 48 steps to reach 1.
18443 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 18444 |
| Euler totient φ(n) | 18442 |
| Square | 340144249 |
| Cube | 6273280384307 |
| Square root | 135.805007 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 48 |
| Scientific notation | 1.8443 × |
18443 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand four hundred and forty-three |
| Binary (base 2) | 100100000001011 |
| Octal (base 8) | 44013 |
| Hexadecimal (base 16) | 480B |
| Base 3 | 221022002 |
| As time | 18443 seconds = 5 h 7 min 23 s |
Is 18443 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 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | 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 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18443 a prime number?
Yes. 18443 is divisible only by 1 and itself.
What are the factors of 18443?
1, 18443.
What is 18443 in binary?
100100000001011 (hexadecimal 480B, octal 44013).
What is the square root of 18443?
About 135.8050.
Is 18443 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 18443?
18443 is the 2113th prime number.