The number 443
443 is the 86th prime number and a binary palindrome (110111011). Its only divisors are 1 and 443.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 443: the 86th prime number; a binary palindrome (110111011).
- 2
443 is prime, so its only factors are 1 and 443. It is the 86th prime; the next prime is 449 and the one before is 439.
- 3
The divisors add up to 444; without 443 itself that is 1, so 443 is deficient (1 is less than 443). Euler's totient φ(443) = 442 numbers up to 443 share no factor with it.
- 4
The digits of 443 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 53 steps to reach 1.
443 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 444 |
| Euler totient φ(n) | 442 |
| Square | 196249 |
| Cube | 86938307 |
| Square root | 21.047565 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 53 |
| Scientific notation | 4.43 × |
443 in other forms
| Form | Value |
|---|---|
| In words | four hundred and forty-three |
| Roman numerals | CDXLIII |
| Binary (base 2) | 110111011 |
| Octal (base 8) | 673 |
| Hexadecimal (base 16) | 1BB |
| Base 3 | 121102 |
| As time | 443 seconds = 7 min 23 s |
Is 443 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 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 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 3) | 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 443 a prime number?
Yes. 443 is divisible only by 1 and itself.
What are the factors of 443?
1, 443.
What is 443 in binary?
110111011 (hexadecimal 1BB, octal 673).
What is the square root of 443?
About 21.0476.
What is 443 in Roman numerals?
CDXLIII.
Is 443 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 443?
443 is the 86th prime number; a binary palindrome (110111011).