The number 31431
31431 is a composite number with 4 divisors. Its prime factorisation is 3 × 10477. Divisors (4): 1, 3, 10477, 31431.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31431: a semiprime: 3 × 10477, the product of two primes.
- 2
31431 is composite. Its prime factorisation is
- 3
The divisors add up to 41912; without 31431 itself that is 10481, so 31431 is deficient (10481 is less than 31431). Euler's totient φ(31431) = 20952 numbers up to 31431 share no factor with it.
- 4
The digits of 31431 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31431 = 3 \times 10477 \]
31431 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 41912 |
| Euler totient φ(n) | 20952 |
| Square | 987907761 |
| Cube | 31050928835991 |
| Square root | 177.287901 |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1431 × |
31431 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand four hundred and thirty-one |
| Binary (base 2) | 111101011000111 |
| Octal (base 8) | 75307 |
| Hexadecimal (base 16) | 7AC7 |
| Base 3 | 1121010010 |
| As time | 31431 seconds = 8 h 43 min 51 s |
Is 31431 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 | Yes (31431 ÷ 3 = 10477) | 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 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31431 a prime number?
No. 31431 = 3 × 10477, so it is divisible by 3.
What are the factors of 31431?
1, 3, 10477, 31431.
What is 31431 in binary?
111101011000111 (hexadecimal 7AC7, octal 75307).
What is the square root of 31431?
About 177.2879.
Is 31431 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 31431?
31431 is a semiprime: 3 × 10477, the product of two primes.