The number 78104
78104 is a composite number with 16 divisors. Its prime factorisation is × 13 × 751. Divisors (16): 1, 2, 4, 8, 13, 26, 52, 104, 751, 1502, 3004, 6008, 9763, 19526, 39052, 78104.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 78104: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
78104 is composite. Its prime factorisation is
- 3
The divisors add up to 157920; without 78104 itself that is 79816, so 78104 is abundant (79816 is more than 78104). Euler's totient φ(78104) = 36000 numbers up to 78104 share no factor with it.
- 4
The digits of 78104 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 138 steps to reach 1.
LaTeX source of the formulas on this page
\[ 78104 = 2^{3} \times 13 \times 751 \]78104 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 157920 |
| Euler totient φ(n) | 36000 |
| Square | 6100234816 |
| Cube | 476452740068864 |
| Square root | 279.470929 (= 2√19526) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 138 |
| Scientific notation | 7.8104 × |
78104 in other forms
| Form | Value |
|---|---|
| In words | seventy-eight thousand one hundred and four |
| Binary (base 2) | 10011000100011000 |
| Octal (base 8) | 230430 |
| Hexadecimal (base 16) | 13118 |
| Base 3 | 10222010202 |
| As time | 78104 seconds = 21 h 41 min 44 s |
Is 78104 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (78104 ÷ 2 = 39052) | 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 | Yes (78104 ÷ 4 = 19526) | 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 2) | 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 | Yes (78104 ÷ 8 = 9763) | 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 | No (remainder 4) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 78104 a prime number?
No. 78104 = × 13 × 751, so it is divisible by 2.
What are the factors of 78104?
1, 2, 4, 8, 13, 26, 52, 104, 751, 1502, 3004, 6008, 9763, 19526, 39052, 78104.
What is 78104 in binary?
10011000100011000 (hexadecimal 13118, octal 230430).
What is the square root of 78104?
About 279.4709, exactly 2√19526.
Is 78104 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 78104?
78104 is a happy number: repeatedly adding the squares of its digits reaches 1.