The number 31427
31427 is a composite number with 4 divisors. Its prime factorisation is 11 × 2857. Divisors (4): 1, 11, 2857, 31427.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31427: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 11 × 2857, the product of two primes.
- 2
31427 is composite. Its prime factorisation is
- 3
The divisors add up to 34296; without 31427 itself that is 2869, so 31427 is deficient (2869 is less than 31427). Euler's totient φ(31427) = 28560 numbers up to 31427 share no factor with it.
- 4
The digits of 31427 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31427 = 11 \times 2857 \]
31427 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 34296 |
| Euler totient φ(n) | 28560 |
| Square | 987656329 |
| Cube | 31039075451483 |
| Square root | 177.276620 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1427 × |
31427 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and twenty-seven |
| Binary (base 2) | 111101011000011 |
| Octal (base 8) | 75303 |
| Hexadecimal (base 16) | 7AC3 |
| Base 3 | 1121002222 |
| As time | 31427 seconds = 8 h 43 min 47 s |
Is 31427 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 2) | 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 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (31427 ÷ 11 = 2857) | 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 31427 a prime number?
No. 31427 = 11 × 2857, so it is divisible by 11.
What are the factors of 31427?
1, 11, 2857, 31427.
What is 31427 in binary?
111101011000011 (hexadecimal 7AC3, octal 75303).
What is the square root of 31427?
About 177.2766.
Is 31427 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 31427?
31427 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 11 × 2857, the product of two primes.