The number 31949
31949 is a composite number with 4 divisors. Its prime factorisation is 43 × 743. Divisors (4): 1, 43, 743, 31949.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31949: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 43 × 743, the product of two primes.
- 2
31949 is composite. Its prime factorisation is
- 3
The divisors add up to 32736; without 31949 itself that is 787, so 31949 is deficient (787 is less than 31949). Euler's totient φ(31949) = 31164 numbers up to 31949 share no factor with it.
- 4
The digits of 31949 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31949 = 43 \times 743 \]
31949 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 32736 |
| Euler totient φ(n) | 31164 |
| Square | 1020738601 |
| Cube | 32611577563349 |
| Square root | 178.742832 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.1949 × |
31949 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand nine hundred and forty-nine |
| Binary (base 2) | 111110011001101 |
| Octal (base 8) | 76315 |
| Hexadecimal (base 16) | 7CCD |
| Base 3 | 1121211022 |
| As time | 31949 seconds = 8 h 52 min 29 s |
Is 31949 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 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 5) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31949 a prime number?
No. 31949 = 43 × 743, so it is divisible by 43.
What are the factors of 31949?
1, 43, 743, 31949.
What is 31949 in binary?
111110011001101 (hexadecimal 7CCD, octal 76315).
What is the square root of 31949?
About 178.7428.
Is 31949 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 31949?
31949 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 43 × 743, the product of two primes.