The number 28142
28142 is a composite number with 4 divisors. Its prime factorisation is 2 × 14071. Divisors (4): 1, 2, 14071, 28142.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 28142: a semiprime: 2 × 14071, the product of two primes.
- 2
28142 is composite. Its prime factorisation is
- 3
The divisors add up to 42216; without 28142 itself that is 14074, so 28142 is deficient (14074 is less than 28142). Euler's totient φ(28142) = 14070 numbers up to 28142 share no factor with it.
- 4
The digits of 28142 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 108 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28142 = 2 \times 14071 \]
28142 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 42216 |
| Euler totient φ(n) | 14070 |
| Square | 791972164 |
| Cube | 22287680639288 |
| Square root | 167.755775 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 108 |
| Scientific notation | 2.8142 × |
28142 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand one hundred and forty-two |
| Binary (base 2) | 110110111101110 |
| Octal (base 8) | 66756 |
| Hexadecimal (base 16) | 6DEE |
| Base 3 | 1102121022 |
| As time | 28142 seconds = 7 h 49 min 2 s |
Is 28142 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28142 ÷ 2 = 14071) | 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 | No (remainder 2) | 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 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 6) | 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 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28142 a prime number?
No. 28142 = 2 × 14071, so it is divisible by 2.
What are the factors of 28142?
1, 2, 14071, 28142.
What is 28142 in binary?
110110111101110 (hexadecimal 6DEE, octal 66756).
What is the square root of 28142?
About 167.7558.
Is 28142 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 28142?
28142 is a semiprime: 2 × 14071, the product of two primes.