The number 78804
78804 is a composite number with 36 divisors. Its prime factorisation is × × 11 × 199. Divisors (36): 1, 2, 3, 4, 6, 9, 11, 12, 18, 22, 33, 36, 44, 66, 99, 132 … 78804.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 78804: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
78804 is composite. Its prime factorisation is
- 3
The divisors add up to 218400; without 78804 itself that is 139596, so 78804 is abundant (139596 is more than 78804). Euler's totient φ(78804) = 23760 numbers up to 78804 share no factor with it.
- 4
The digits of 78804 add up to 27, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 76 steps to reach 1.
LaTeX source of the formulas on this page
\[ 78804 = 2^{2} \times 3^{2} \times 11 \times 199 \]78804 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 36 |
| Sum of divisors | 218400 |
| Euler totient φ(n) | 23760 |
| Square | 6210070416 |
| Cube | 489378389062464 |
| Square root | 280.720502 (= 6√2189) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 76 |
| Scientific notation | 7.8804 × |
78804 in other forms
| Form | Value |
|---|---|
| In words | seventy-eight thousand eight hundred and four |
| Binary (base 2) | 10011001111010100 |
| Octal (base 8) | 231724 |
| Hexadecimal (base 16) | 133D4 |
| Base 3 | 11000002200 |
| As time | 78804 seconds = 21 h 53 min 24 s |
Is 78804 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (78804 ÷ 2 = 39402) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (78804 ÷ 3 = 26268) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (78804 ÷ 4 = 19701) | 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 | Yes (78804 ÷ 6 = 13134) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (78804 ÷ 9 = 8756) | 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 | Yes (78804 ÷ 11 = 7164) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (78804 ÷ 12 = 6567) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 78804 a prime number?
No. 78804 = × × 11 × 199, so it is divisible by 2.
What are the factors of 78804?
1, 2, 3, 4, 6, 9, 11, 12, 18, 22, 33, 36, 44, 66, 99, 132, 198, 199, 396, 398, 597, 796, 1194, 1791, 2189, 2388, 3582, 4378, 6567, 7164, 8756, 13134, 19701, 26268, 39402, 78804.
What is 78804 in binary?
10011001111010100 (hexadecimal 133D4, octal 231724).
What is the square root of 78804?
About 280.7205, exactly 6√2189.
Is 78804 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 78804?
78804 is a happy number: repeatedly adding the squares of its digits reaches 1.