The number 27808
27808 is a composite number with 24 divisors. Its prime factorisation is × 11 × 79. Divisors (24): 1, 2, 4, 8, 11, 16, 22, 32, 44, 79, 88, 158, 176, 316, 352, 632 … 27808.
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How to work it out
- 1
27808 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
27808 is composite. Its prime factorisation is
- 3
The divisors add up to 60480; without 27808 itself that is 32672, so 27808 is abundant (32672 is more than 27808). Euler's totient φ(27808) = 12480 numbers up to 27808 share no factor with it.
- 4
The digits of 27808 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 33 steps to reach 1.
LaTeX source of the formulas on this page
\[ 27808 = 2^{5} \times 11 \times 79 \]27808 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 60480 |
| Euler totient φ(n) | 12480 |
| Square | 773284864 |
| Cube | 21503505498112 |
| Square root | 166.757309 (= 4√1738) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 33 |
| Scientific notation | 2.7808 × |
27808 in other forms
| Form | Value |
|---|---|
| In words | twenty-seven thousand eight hundred and eight |
| Binary (base 2) | 110110010100000 |
| Octal (base 8) | 66240 |
| Hexadecimal (base 16) | 6CA0 |
| Base 3 | 1102010221 |
| As time | 27808 seconds = 7 h 43 min 28 s |
Is 27808 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (27808 ÷ 2 = 13904) | 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 (27808 ÷ 4 = 6952) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | 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 (27808 ÷ 8 = 3476) | 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 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (27808 ÷ 11 = 2528) | 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 27808 a prime number?
No. 27808 = × 11 × 79, so it is divisible by 2.
What are the factors of 27808?
1, 2, 4, 8, 11, 16, 22, 32, 44, 79, 88, 158, 176, 316, 352, 632, 869, 1264, 1738, 2528, 3476, 6952, 13904, 27808.
What is 27808 in binary?
110110010100000 (hexadecimal 6CA0, octal 66240).
What is the square root of 27808?
About 166.7573, exactly 4√1738.
Is 27808 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 27808?
It is a composite number with 24 divisors.