The number 31970
31970 is a composite number with 16 divisors. Its prime factorisation is 2 × 5 × 23 × 139. Divisors (16): 1, 2, 5, 10, 23, 46, 115, 139, 230, 278, 695, 1390, 3197, 6394, 15985, 31970.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31970 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31970 is composite. Its prime factorisation is
- 3
The divisors add up to 60480; without 31970 itself that is 28510, so 31970 is deficient (28510 is less than 31970). Euler's totient φ(31970) = 12144 numbers up to 31970 share no factor with it.
- 4
The digits of 31970 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31970 = 2 \times 5 \times 23 \times 139 \]
31970 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 60480 |
| Euler totient φ(n) | 12144 |
| Square | 1022080900 |
| Cube | 32675926373000 |
| Square root | 178.801566 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.197 × |
31970 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand nine hundred and seventy |
| Binary (base 2) | 111110011100010 |
| Octal (base 8) | 76342 |
| Hexadecimal (base 16) | 7CE2 |
| Base 3 | 1121212002 |
| As time | 31970 seconds = 8 h 52 min 50 s |
Is 31970 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31970 ÷ 2 = 15985) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (31970 ÷ 5 = 6394) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (31970 ÷ 10 = 3197) | 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 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31970 a prime number?
No. 31970 = 2 × 5 × 23 × 139, so it is divisible by 2.
What are the factors of 31970?
1, 2, 5, 10, 23, 46, 115, 139, 230, 278, 695, 1390, 3197, 6394, 15985, 31970.
What is 31970 in binary?
111110011100010 (hexadecimal 7CE2, octal 76342).
What is the square root of 31970?
About 178.8016.
Is 31970 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 31970?
It is a composite number with 16 divisors.