The number 39904
39904 is a composite number with 24 divisors. Its prime factorisation is × 29 × 43. Divisors (24): 1, 2, 4, 8, 16, 29, 32, 43, 58, 86, 116, 172, 232, 344, 464, 688 … 39904.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
39904 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
39904 is composite. Its prime factorisation is
- 3
The divisors add up to 83160; without 39904 itself that is 43256, so 39904 is abundant (43256 is more than 39904). Euler's totient φ(39904) = 18816 numbers up to 39904 share no factor with it.
- 4
The digits of 39904 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 137 steps to reach 1.
LaTeX source of the formulas on this page
\[ 39904 = 2^{5} \times 29 \times 43 \]39904 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 83160 |
| Euler totient φ(n) | 18816 |
| Square | 1592329216 |
| Cube | 63540305035264 |
| Square root | 199.759856 (= 4√2494) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 137 |
| Scientific notation | 3.9904 × |
39904 in other forms
| Form | Value |
|---|---|
| In words | thirty-nine thousand nine hundred and four |
| Binary (base 2) | 1001101111100000 |
| Octal (base 8) | 115740 |
| Hexadecimal (base 16) | 9BE0 |
| Base 3 | 2000201221 |
| As time | 39904 seconds = 11 h 5 min 4 s |
Is 39904 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (39904 ÷ 2 = 19952) | 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 (39904 ÷ 4 = 9976) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | 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 (39904 ÷ 8 = 4988) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 39904 a prime number?
No. 39904 = × 29 × 43, so it is divisible by 2.
What are the factors of 39904?
1, 2, 4, 8, 16, 29, 32, 43, 58, 86, 116, 172, 232, 344, 464, 688, 928, 1247, 1376, 2494, 4988, 9976, 19952, 39904.
What is 39904 in binary?
1001101111100000 (hexadecimal 9BE0, octal 115740).
What is the square root of 39904?
About 199.7599, exactly 4√2494.
Is 39904 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 39904?
It is a composite number with 24 divisors.