The number 28080
28080 is a composite number with 80 divisors. Its prime factorisation is × × 5 × 13. Divisors (80): 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 13, 15, 16, 18, 20, 24 … 28080.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 28080: a Harshad number: divisible by its digit sum 18.
- 2
28080 is composite. Its prime factorisation is
- 3
The divisors add up to 104160; without 28080 itself that is 76080, so 28080 is abundant (76080 is more than 28080). Euler's totient φ(28080) = 6912 numbers up to 28080 share no factor with it.
- 4
The digits of 28080 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 46 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28080 = 2^{4} \times 3^{3} \times 5 \times 13 \]28080 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 80 |
| Sum of divisors | 104160 |
| Euler totient φ(n) | 6912 |
| Square | 788486400 |
| Cube | 22140698112000 |
| Square root | 167.570881 (= 12√195) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 46 |
| Scientific notation | 2.808 × |
28080 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand and eighty |
| Binary (base 2) | 110110110110000 |
| Octal (base 8) | 66660 |
| Hexadecimal (base 16) | 6DB0 |
| Base 3 | 1102112000 |
| As time | 28080 seconds = 7 h 48 min 0 s |
Is 28080 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28080 ÷ 2 = 14040) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (28080 ÷ 3 = 9360) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (28080 ÷ 4 = 7020) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (28080 ÷ 5 = 5616) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (28080 ÷ 6 = 4680) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 (28080 ÷ 8 = 3510) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (28080 ÷ 9 = 3120) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (28080 ÷ 10 = 2808) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (28080 ÷ 12 = 2340) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28080 a prime number?
No. 28080 = × × 5 × 13, so it is divisible by 2.
What are the factors of 28080?
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 13, 15, 16, 18, 20, 24, 26, 27, 30, 36, 39, 40, 45, 48, 52, 54, 60, 65, 72, 78, 80, 90, 104, 108, 117, 120, 130, 135, 144, 156, 180, 195, 208, 216, 234, 240, 260, 270, 312, 351, 360, 390, 432, 468, 520, 540, 585, 624, 702, 720, 780, 936, 1040, 1080, 1170, 1404, 1560, 1755, 1872, 2160, 2340, 2808, 3120, 3510, 4680, 5616, 7020, 9360, 14040, 28080.
What is 28080 in binary?
110110110110000 (hexadecimal 6DB0, octal 66660).
What is the square root of 28080?
About 167.5709, exactly 12√195.
Is 28080 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 28080?
28080 is a Harshad number: divisible by its digit sum 18.