The number 77445
77445 is a composite number with 12 divisors. Its prime factorisation is × 5 × 1721. Divisors (12): 1, 3, 5, 9, 15, 45, 1721, 5163, 8605, 15489, 25815, 77445.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
77445 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
77445 is composite. Its prime factorisation is
- 3
The divisors add up to 134316; without 77445 itself that is 56871, so 77445 is deficient (56871 is less than 77445). Euler's totient φ(77445) = 41280 numbers up to 77445 share no factor with it.
- 4
The digits of 77445 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 76 steps to reach 1.
LaTeX source of the formulas on this page
\[ 77445 = 3^{2} \times 5 \times 1721 \]77445 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 134316 |
| Euler totient φ(n) | 41280 |
| Square | 5997728025 |
| Cube | 464494046896125 |
| Square root | 278.289418 (= 3√8605) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 76 |
| Scientific notation | 7.7445 × |
77445 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand four hundred and forty-five |
| Binary (base 2) | 10010111010000101 |
| Octal (base 8) | 227205 |
| Hexadecimal (base 16) | 12E85 |
| Base 3 | 10221020100 |
| As time | 77445 seconds = 21 h 30 min 45 s |
Is 77445 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 (77445 ÷ 3 = 25815) | 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 | Yes (77445 ÷ 5 = 15489) | 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 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 | No (remainder 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (77445 ÷ 9 = 8605) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 77445 a prime number?
No. 77445 = × 5 × 1721, so it is divisible by 3.
What are the factors of 77445?
1, 3, 5, 9, 15, 45, 1721, 5163, 8605, 15489, 25815, 77445.
What is 77445 in binary?
10010111010000101 (hexadecimal 12E85, octal 227205).
What is the square root of 77445?
About 278.2894, exactly 3√8605.
Is 77445 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 77445?
It is a composite number with 12 divisors.