The number 27761
27761 is a composite number with 8 divisors. Its prime factorisation is 17 × 23 × 71. Divisors (8): 1, 17, 23, 71, 391, 1207, 1633, 27761.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 27761: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23.
- 2
27761 is composite. Its prime factorisation is
- 3
The divisors add up to 31104; without 27761 itself that is 3343, so 27761 is deficient (3343 is less than 27761). Euler's totient φ(27761) = 24640 numbers up to 27761 share no factor with it.
- 4
The digits of 27761 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 33 steps to reach 1.
LaTeX source of the formulas on this page
\[ 27761 = 17 \times 23 \times 71 \]
27761 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 31104 |
| Euler totient φ(n) | 24640 |
| Square | 770673121 |
| Cube | 21394656512081 |
| Square root | 166.616326 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 33 |
| Scientific notation | 2.7761 × |
27761 in other forms
| Form | Value |
|---|---|
| In words | twenty-seven thousand seven hundred and sixty-one |
| Binary (base 2) | 110110001110001 |
| Octal (base 8) | 66161 |
| Hexadecimal (base 16) | 6C71 |
| Base 3 | 1102002012 |
| As time | 27761 seconds = 7 h 42 min 41 s |
Is 27761 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 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 1) | 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 | No (remainder 1) | 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 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 27761 a prime number?
No. 27761 = 17 × 23 × 71, so it is divisible by 17.
What are the factors of 27761?
1, 17, 23, 71, 391, 1207, 1633, 27761.
What is 27761 in binary?
110110001110001 (hexadecimal 6C71, octal 66161).
What is the square root of 27761?
About 166.6163.
Is 27761 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 27761?
27761 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23.