The number 78080
78080 is a composite number with 36 divisors. Its prime factorisation is × 5 × 61. Divisors (36): 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 61, 64, 80, 122, 128, 160 … 78080.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
78080 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
78080 is composite. Its prime factorisation is
- 3
The divisors add up to 190092; without 78080 itself that is 112012, so 78080 is abundant (112012 is more than 78080). Euler's totient φ(78080) = 30720 numbers up to 78080 share no factor with it.
- 4
The digits of 78080 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 45 steps to reach 1.
LaTeX source of the formulas on this page
\[ 78080 = 2^{8} \times 5 \times 61 \]78080 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 36 |
| Sum of divisors | 190092 |
| Euler totient φ(n) | 30720 |
| Square | 6096486400 |
| Cube | 476013658112000 |
| Square root | 279.427987 (= 16√305) |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 45 |
| Scientific notation | 7.808 × |
78080 in other forms
| Form | Value |
|---|---|
| In words | seventy-eight thousand and eighty |
| Binary (base 2) | 10011000100000000 |
| Octal (base 8) | 230400 |
| Hexadecimal (base 16) | 13100 |
| Base 3 | 10222002212 |
| As time | 78080 seconds = 21 h 41 min 20 s |
Is 78080 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (78080 ÷ 2 = 39040) | 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 (78080 ÷ 4 = 19520) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (78080 ÷ 5 = 15616) | 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 2) | 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 (78080 ÷ 8 = 9760) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (78080 ÷ 10 = 7808) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | 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 78080 a prime number?
No. 78080 = × 5 × 61, so it is divisible by 2.
What are the factors of 78080?
1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 61, 64, 80, 122, 128, 160, 244, 256, 305, 320, 488, 610, 640, 976, 1220, 1280, 1952, 2440, 3904, 4880, 7808, 9760, 15616, 19520, 39040, 78080.
What is 78080 in binary?
10011000100000000 (hexadecimal 13100, octal 230400).
What is the square root of 78080?
About 279.4280, exactly 16√305.
Is 78080 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 78080?
It is a composite number with 36 divisors.