The number 5731
5731 is a composite number with 4 divisors. Its prime factorisation is 11 × 521. Divisors (4): 1, 11, 521, 5731.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 5731: a semiprime: 11 × 521, the product of two primes.
- 2
5731 is composite. Its prime factorisation is
- 3
The divisors add up to 6264; without 5731 itself that is 533, so 5731 is deficient (533 is less than 5731). Euler's totient φ(5731) = 5200 numbers up to 5731 share no factor with it.
- 4
The digits of 5731 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 28 steps to reach 1.
LaTeX source of the formulas on this page
\[ 5731 = 11 \times 521 \]
5731 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 6264 |
| Euler totient φ(n) | 5200 |
| Square | 32844361 |
| Cube | 188231032891 |
| Square root | 75.703368 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 28 |
| Scientific notation | 5.731 × |
5731 in other forms
| Form | Value |
|---|---|
| In words | five thousand seven hundred and thirty-one |
| Binary (base 2) | 1011001100011 |
| Octal (base 8) | 13143 |
| Hexadecimal (base 16) | 1663 |
| Base 3 | 21212021 |
| As time | 5731 seconds = 1 h 35 min 31 s |
Is 5731 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 3) | 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 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 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 | Yes (5731 ÷ 11 = 521) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 5731 a prime number?
No. 5731 = 11 × 521, so it is divisible by 11.
What are the factors of 5731?
1, 11, 521, 5731.
What is 5731 in binary?
1011001100011 (hexadecimal 1663, octal 13143).
What is the square root of 5731?
About 75.7034.
Is 5731 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 5731?
5731 is a semiprime: 11 × 521, the product of two primes.