The number 12428
12428 is a composite number with 12 divisors. Its prime factorisation is × 13 × 239. Divisors (12): 1, 2, 4, 13, 26, 52, 239, 478, 956, 3107, 6214, 12428.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
12428 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
12428 is composite. Its prime factorisation is
- 3
The divisors add up to 23520; without 12428 itself that is 11092, so 12428 is deficient (11092 is less than 12428). Euler's totient φ(12428) = 5712 numbers up to 12428 share no factor with it.
- 4
The digits of 12428 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 125 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12428 = 2^{2} \times 13 \times 239 \]12428 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 23520 |
| Euler totient φ(n) | 5712 |
| Square | 154455184 |
| Cube | 1919569026752 |
| Square root | 111.480940 (= 2√3107) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 125 |
| Scientific notation | 1.2428 × |
12428 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand four hundred and twenty-eight |
| Binary (base 2) | 11000010001100 |
| Octal (base 8) | 30214 |
| Hexadecimal (base 16) | 308C |
| Base 3 | 122001022 |
| As time | 12428 seconds = 3 h 27 min 8 s |
Is 12428 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (12428 ÷ 2 = 6214) | 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 | Yes (12428 ÷ 4 = 3107) | 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 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 4) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | 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 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 12428 a prime number?
No. 12428 = × 13 × 239, so it is divisible by 2.
What are the factors of 12428?
1, 2, 4, 13, 26, 52, 239, 478, 956, 3107, 6214, 12428.
What is 12428 in binary?
11000010001100 (hexadecimal 308C, octal 30214).
What is the square root of 12428?
About 111.4809, exactly 2√3107.
Is 12428 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 12428?
It is a composite number with 12 divisors.