The number 28424
28424 is a composite number with 32 divisors. Its prime factorisation is × 11 × 17 × 19. Divisors (32): 1, 2, 4, 8, 11, 17, 19, 22, 34, 38, 44, 68, 76, 88, 136, 152 … 28424.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
28424 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
28424 is composite. Its prime factorisation is
- 3
The divisors add up to 64800; without 28424 itself that is 36376, so 28424 is abundant (36376 is more than 28424). Euler's totient φ(28424) = 11520 numbers up to 28424 share no factor with it.
- 4
The digits of 28424 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 59 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28424 = 2^{3} \times 11 \times 17 \times 19 \]28424 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 64800 |
| Euler totient φ(n) | 11520 |
| Square | 807923776 |
| Cube | 22964425409024 |
| Square root | 168.594187 (= 2√7106) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 59 |
| Scientific notation | 2.8424 × |
28424 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand four hundred and twenty-four |
| Binary (base 2) | 110111100001000 |
| Octal (base 8) | 67410 |
| Hexadecimal (base 16) | 6F08 |
| Base 3 | 1102222202 |
| As time | 28424 seconds = 7 h 53 min 44 s |
Is 28424 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28424 ÷ 2 = 14212) | 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 (28424 ÷ 4 = 7106) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 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 | Yes (28424 ÷ 8 = 3553) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (28424 ÷ 11 = 2584) | 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 28424 a prime number?
No. 28424 = × 11 × 17 × 19, so it is divisible by 2.
What are the factors of 28424?
1, 2, 4, 8, 11, 17, 19, 22, 34, 38, 44, 68, 76, 88, 136, 152, 187, 209, 323, 374, 418, 646, 748, 836, 1292, 1496, 1672, 2584, 3553, 7106, 14212, 28424.
What is 28424 in binary?
110111100001000 (hexadecimal 6F08, octal 67410).
What is the square root of 28424?
About 168.5942, exactly 2√7106.
Is 28424 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 28424?
It is a composite number with 32 divisors.