The number 28672
28672 is a composite number with 26 divisors. Its prime factorisation is × 7. Divisors (26): 1, 2, 4, 7, 8, 14, 16, 28, 32, 56, 64, 112, 128, 224, 256, 448 … 28672.
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How to work it out
- 1
28672 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
28672 is composite. Its prime factorisation is
- 3
The divisors add up to 65528; without 28672 itself that is 36856, so 28672 is abundant (36856 is more than 28672). Euler's totient φ(28672) = 12288 numbers up to 28672 share no factor with it.
- 4
The digits of 28672 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 28 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28672 = 2^{12} \times 7 \]28672 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 26 |
| Sum of divisors | 65528 |
| Euler totient φ(n) | 12288 |
| Square | 822083584 |
| Cube | 23570780520448 |
| Square root | 169.328084 (= 64√7) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 28 |
| Scientific notation | 2.8672 × |
28672 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand six hundred and seventy-two |
| Binary (base 2) | 111000000000000 |
| Octal (base 8) | 70000 |
| Hexadecimal (base 16) | 7000 |
| Base 3 | 1110022221 |
| As time | 28672 seconds = 7 h 57 min 52 s |
Is 28672 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28672 ÷ 2 = 14336) | 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 | Yes (28672 ÷ 4 = 7168) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (28672 ÷ 7 = 4096) | 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 (28672 ÷ 8 = 3584) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28672 a prime number?
No. 28672 = × 7, so it is divisible by 2.
What are the factors of 28672?
1, 2, 4, 7, 8, 14, 16, 28, 32, 56, 64, 112, 128, 224, 256, 448, 512, 896, 1024, 1792, 2048, 3584, 4096, 7168, 14336, 28672.
What is 28672 in binary?
111000000000000 (hexadecimal 7000, octal 70000).
What is the square root of 28672?
About 169.3281, exactly 64√7.
Is 28672 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 28672?
It is a composite number with 26 divisors.