The number 27855
27855 is a composite number with 12 divisors. Its prime factorisation is × 5 × 619. Divisors (12): 1, 3, 5, 9, 15, 45, 619, 1857, 3095, 5571, 9285, 27855.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 27855: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
27855 is composite. Its prime factorisation is
- 3
The divisors add up to 48360; without 27855 itself that is 20505, so 27855 is deficient (20505 is less than 27855). Euler's totient φ(27855) = 14832 numbers up to 27855 share no factor with it.
- 4
The digits of 27855 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 64 steps to reach 1.
LaTeX source of the formulas on this page
\[ 27855 = 3^{2} \times 5 \times 619 \]27855 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 48360 |
| Euler totient φ(n) | 14832 |
| Square | 775901025 |
| Cube | 21612723051375 |
| Square root | 166.898173 (= 3√3095) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 64 |
| Scientific notation | 2.7855 × |
27855 in other forms
| Form | Value |
|---|---|
| In words | twenty-seven thousand eight hundred and fifty-five |
| Binary (base 2) | 110110011001111 |
| Octal (base 8) | 66317 |
| Hexadecimal (base 16) | 6CCF |
| Base 3 | 1102012200 |
| As time | 27855 seconds = 7 h 44 min 15 s |
Is 27855 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (27855 ÷ 3 = 9285) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (27855 ÷ 5 = 5571) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | 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 | No (remainder 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (27855 ÷ 9 = 3095) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 27855 a prime number?
No. 27855 = × 5 × 619, so it is divisible by 3.
What are the factors of 27855?
1, 3, 5, 9, 15, 45, 619, 1857, 3095, 5571, 9285, 27855.
What is 27855 in binary?
110110011001111 (hexadecimal 6CCF, octal 66317).
What is the square root of 27855?
About 166.8982, exactly 3√3095.
Is 27855 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 27855?
27855 is a happy number: repeatedly adding the squares of its digits reaches 1.