The number 3131
3131 is a composite number with 4 divisors. Its prime factorisation is 31 × 101. Divisors (4): 1, 31, 101, 3131.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 3131: a semiprime: 31 × 101, the product of two primes.
- 2
3131 is composite. Its prime factorisation is
- 3
The divisors add up to 3264; without 3131 itself that is 133, so 3131 is deficient (133 is less than 3131). Euler's totient φ(3131) = 3000 numbers up to 3131 share no factor with it.
- 4
The digits of 3131 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 110 steps to reach 1.
LaTeX source of the formulas on this page
\[ 3131 = 31 \times 101 \]
3131 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 3264 |
| Euler totient φ(n) | 3000 |
| Square | 9803161 |
| Cube | 30693697091 |
| Square root | 55.955339 |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 110 |
| Scientific notation | 3.131 × |
3131 in other forms
| Form | Value |
|---|---|
| In words | three thousand one hundred and thirty-one |
| Roman numerals | MMMCXXXI |
| Binary (base 2) | 110000111011 |
| Octal (base 8) | 6073 |
| Hexadecimal (base 16) | C3B |
| Base 3 | 11021222 |
| As time | 3131 seconds = 52 min 11 s |
Is 3131 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 1) | 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 8) | 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 7) | 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 3131 a prime number?
No. 3131 = 31 × 101, so it is divisible by 31.
What are the factors of 3131?
1, 31, 101, 3131.
What is 3131 in binary?
110000111011 (hexadecimal C3B, octal 6073).
What is the square root of 3131?
About 55.9553.
What is 3131 in Roman numerals?
MMMCXXXI.
Is 3131 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 3131?
3131 is a semiprime: 31 × 101, the product of two primes.