The number 77818
77818 is a composite number with 16 divisors. Its prime factorisation is 2 × 13 × 41 × 73. Divisors (16): 1, 2, 13, 26, 41, 73, 82, 146, 533, 949, 1066, 1898, 2993, 5986, 38909, 77818.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
77818 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
77818 is composite. Its prime factorisation is
- 3
The divisors add up to 130536; without 77818 itself that is 52718, so 77818 is deficient (52718 is less than 77818). Euler's totient φ(77818) = 34560 numbers up to 77818 share no factor with it.
- 4
The digits of 77818 add up to 31, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 94 steps to reach 1.
LaTeX source of the formulas on this page
\[ 77818 = 2 \times 13 \times 41 \times 73 \]
77818 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 130536 |
| Euler totient φ(n) | 34560 |
| Square | 6055641124 |
| Cube | 471237880987432 |
| Square root | 278.958778 |
| Digit sum / digital root | 31 / 4 |
| Collatz steps to 1 | 94 |
| Scientific notation | 7.7818 × |
77818 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand eight hundred and eighteen |
| Binary (base 2) | 10010111111111010 |
| Octal (base 8) | 227772 |
| Hexadecimal (base 16) | 12FFA |
| Base 3 | 10221202011 |
| As time | 77818 seconds = 21 h 36 min 58 s |
Is 77818 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (77818 ÷ 2 = 38909) | 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 2) | 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 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | 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 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 77818 a prime number?
No. 77818 = 2 × 13 × 41 × 73, so it is divisible by 2.
What are the factors of 77818?
1, 2, 13, 26, 41, 73, 82, 146, 533, 949, 1066, 1898, 2993, 5986, 38909, 77818.
What is 77818 in binary?
10010111111111010 (hexadecimal 12FFA, octal 227772).
What is the square root of 77818?
About 278.9588.
Is 77818 divisible by 3?
No. Its digits add up to 31, which is not a multiple of 3.
What is special about the number 77818?
It is a composite number with 16 divisors.