The number 28143
28143 is a composite number with 12 divisors. Its prime factorisation is × 53 × 59. Divisors (12): 1, 3, 9, 53, 59, 159, 177, 477, 531, 3127, 9381, 28143.
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How to work it out
- 1
What is special about 28143: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
28143 is composite. Its prime factorisation is
- 3
The divisors add up to 42120; without 28143 itself that is 13977, so 28143 is deficient (13977 is less than 28143). Euler's totient φ(28143) = 18096 numbers up to 28143 share no factor with it.
- 4
The digits of 28143 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 82 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28143 = 3^{2} \times 53 \times 59 \]28143 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 42120 |
| Euler totient φ(n) | 18096 |
| Square | 792028449 |
| Cube | 22290056640207 |
| Square root | 167.758755 (= 3√3127) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 82 |
| Scientific notation | 2.8143 × |
28143 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand one hundred and forty-three |
| Binary (base 2) | 110110111101111 |
| Octal (base 8) | 66757 |
| Hexadecimal (base 16) | 6DEF |
| Base 3 | 1102121100 |
| As time | 28143 seconds = 7 h 49 min 3 s |
Is 28143 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 (28143 ÷ 3 = 9381) | 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 3) | 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 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (28143 ÷ 9 = 3127) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 3) | 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 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28143 a prime number?
No. 28143 = × 53 × 59, so it is divisible by 3.
What are the factors of 28143?
1, 3, 9, 53, 59, 159, 177, 477, 531, 3127, 9381, 28143.
What is 28143 in binary?
110110111101111 (hexadecimal 6DEF, octal 66757).
What is the square root of 28143?
About 167.7588, exactly 3√3127.
Is 28143 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 28143?
28143 is a happy number: repeatedly adding the squares of its digits reaches 1.