The number 77427
77427 is a composite number with 12 divisors. Its prime factorisation is × 7 × 1229. Divisors (12): 1, 3, 7, 9, 21, 63, 1229, 3687, 8603, 11061, 25809, 77427.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 77427: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
77427 is composite. Its prime factorisation is
- 3
The divisors add up to 127920; without 77427 itself that is 50493, so 77427 is deficient (50493 is less than 77427). Euler's totient φ(77427) = 44208 numbers up to 77427 share no factor with it.
- 4
The digits of 77427 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 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 77427 = 3^{2} \times 7 \times 1229 \]77427 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 127920 |
| Euler totient φ(n) | 44208 |
| Square | 5994940329 |
| Cube | 464170244853483 |
| Square root | 278.257075 (= 3√8603) |
| Digit sum / digital root | 27 / 9 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.7427 × |
77427 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand four hundred and twenty-seven |
| Binary (base 2) | 10010111001110011 |
| Octal (base 8) | 227163 |
| Hexadecimal (base 16) | 12E73 |
| Base 3 | 10221012200 |
| As time | 77427 seconds = 21 h 30 min 27 s |
Is 77427 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 (77427 ÷ 3 = 25809) | 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 | No (remainder 2) | 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 | Yes (77427 ÷ 7 = 11061) | 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 | Yes (77427 ÷ 9 = 8603) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 77427 a prime number?
No. 77427 = × 7 × 1229, so it is divisible by 3.
What are the factors of 77427?
1, 3, 7, 9, 21, 63, 1229, 3687, 8603, 11061, 25809, 77427.
What is 77427 in binary?
10010111001110011 (hexadecimal 12E73, octal 227163).
What is the square root of 77427?
About 278.2571, exactly 3√8603.
Is 77427 divisible by 3?
Yes. Its digits add up to 27, a multiple of 3.
What is special about the number 77427?
77427 is a happy number: repeatedly adding the squares of its digits reaches 1.