The number 31648
31648 is a composite number with 24 divisors. Its prime factorisation is × 23 × 43. Divisors (24): 1, 2, 4, 8, 16, 23, 32, 43, 46, 86, 92, 172, 184, 344, 368, 688 … 31648.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31648 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31648 is composite. Its prime factorisation is
- 3
The divisors add up to 66528; without 31648 itself that is 34880, so 31648 is abundant (34880 is more than 31648). Euler's totient φ(31648) = 14784 numbers up to 31648 share no factor with it.
- 4
The digits of 31648 add up to 22, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31648 = 2^{5} \times 23 \times 43 \]31648 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 66528 |
| Euler totient φ(n) | 14784 |
| Square | 1001595904 |
| Cube | 31698507169792 |
| Square root | 177.898848 (= 4√1978) |
| Digit sum / digital root | 22 / 4 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.1648 × |
31648 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand six hundred and forty-eight |
| Binary (base 2) | 111101110100000 |
| Octal (base 8) | 75640 |
| Hexadecimal (base 16) | 7BA0 |
| Base 3 | 1121102011 |
| As time | 31648 seconds = 8 h 47 min 28 s |
Is 31648 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31648 ÷ 2 = 15824) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (31648 ÷ 4 = 7912) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | 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 | Yes (31648 ÷ 8 = 3956) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31648 a prime number?
No. 31648 = × 23 × 43, so it is divisible by 2.
What are the factors of 31648?
1, 2, 4, 8, 16, 23, 32, 43, 46, 86, 92, 172, 184, 344, 368, 688, 736, 989, 1376, 1978, 3956, 7912, 15824, 31648.
What is 31648 in binary?
111101110100000 (hexadecimal 7BA0, octal 75640).
What is the square root of 31648?
About 177.8988, exactly 4√1978.
Is 31648 divisible by 3?
No. Its digits add up to 22, which is not a multiple of 3.
What is special about the number 31648?
It is a composite number with 24 divisors.