The number 77155
77155 is a composite number with 8 divisors. Its prime factorisation is 5 × 13 × 1187. Divisors (8): 1, 5, 13, 65, 1187, 5935, 15431, 77155.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
77155 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
77155 is composite. Its prime factorisation is
- 3
The divisors add up to 99792; without 77155 itself that is 22637, so 77155 is deficient (22637 is less than 77155). Euler's totient φ(77155) = 56928 numbers up to 77155 share no factor with it.
- 4
The digits of 77155 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 169 steps to reach 1.
LaTeX source of the formulas on this page
\[ 77155 = 5 \times 13 \times 1187 \]
77155 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 99792 |
| Euler totient φ(n) | 56928 |
| Square | 5952894025 |
| Cube | 459295538498875 |
| Square root | 277.767889 |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 169 |
| Scientific notation | 7.7155 × |
77155 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand one hundred and fifty-five |
| Binary (base 2) | 10010110101100011 |
| Octal (base 8) | 226543 |
| Hexadecimal (base 16) | 12D63 |
| Base 3 | 10220211121 |
| As time | 77155 seconds = 21 h 25 min 55 s |
Is 77155 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 1) | 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 (77155 ÷ 5 = 15431) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 3) | 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 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 77155 a prime number?
No. 77155 = 5 × 13 × 1187, so it is divisible by 5.
What are the factors of 77155?
1, 5, 13, 65, 1187, 5935, 15431, 77155.
What is 77155 in binary?
10010110101100011 (hexadecimal 12D63, octal 226543).
What is the square root of 77155?
About 277.7679.
Is 77155 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 77155?
It is a composite number with 8 divisors.