The number 4381
4381 is a composite number with 4 divisors. Its prime factorisation is 13 × 337. Divisors (4): 1, 13, 337, 4381.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 4381: a semiprime: 13 × 337, the product of two primes.
- 2
4381 is composite. Its prime factorisation is
- 3
The divisors add up to 4732; without 4381 itself that is 351, so 4381 is deficient (351 is less than 4381). Euler's totient φ(4381) = 4032 numbers up to 4381 share no factor with it.
- 4
The digits of 4381 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 77 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4381 = 13 \times 337 \]
4381 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 4732 |
| Euler totient φ(n) | 4032 |
| Square | 19193161 |
| Cube | 84085238341 |
| Square root | 66.189123 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 77 |
| Scientific notation | 4.381 × |
4381 in other forms
| Form | Value |
|---|---|
| In words | four thousand three hundred and eighty-one |
| Binary (base 2) | 1000100011101 |
| Octal (base 8) | 10435 |
| Hexadecimal (base 16) | 111D |
| Base 3 | 20000021 |
| As time | 4381 seconds = 1 h 13 min 1 s |
Is 4381 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 1) | 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 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 4381 a prime number?
No. 4381 = 13 × 337, so it is divisible by 13.
What are the factors of 4381?
1, 13, 337, 4381.
What is 4381 in binary?
1000100011101 (hexadecimal 111D, octal 10435).
What is the square root of 4381?
About 66.1891.
Is 4381 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 4381?
4381 is a semiprime: 13 × 337, the product of two primes.