The number 42028
42028 is a composite number with 24 divisors. Its prime factorisation is × 7 × 19 × 79. Divisors (24): 1, 2, 4, 7, 14, 19, 28, 38, 76, 79, 133, 158, 266, 316, 532, 553 … 42028.
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How to work it out
- 1
42028 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
42028 is composite. Its prime factorisation is
- 3
The divisors add up to 89600; without 42028 itself that is 47572, so 42028 is abundant (47572 is more than 42028). Euler's totient φ(42028) = 16848 numbers up to 42028 share no factor with it.
- 4
The digits of 42028 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 150 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42028 = 2^{2} \times 7 \times 19 \times 79 \]42028 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 89600 |
| Euler totient φ(n) | 16848 |
| Square | 1766352784 |
| Cube | 74236274805952 |
| Square root | 205.007317 (= 2√10507) |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 150 |
| Scientific notation | 4.2028 × |
42028 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and twenty-eight |
| Binary (base 2) | 1010010000101100 |
| Octal (base 8) | 122054 |
| Hexadecimal (base 16) | A42C |
| Base 3 | 2010122121 |
| As time | 42028 seconds = 11 h 40 min 28 s |
Is 42028 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42028 ÷ 2 = 21014) | 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 (42028 ÷ 4 = 10507) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (42028 ÷ 7 = 6004) | 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 7) | 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 8) | 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 42028 a prime number?
No. 42028 = × 7 × 19 × 79, so it is divisible by 2.
What are the factors of 42028?
1, 2, 4, 7, 14, 19, 28, 38, 76, 79, 133, 158, 266, 316, 532, 553, 1106, 1501, 2212, 3002, 6004, 10507, 21014, 42028.
What is 42028 in binary?
1010010000101100 (hexadecimal A42C, octal 122054).
What is the square root of 42028?
About 205.0073, exactly 2√10507.
Is 42028 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 42028?
It is a composite number with 24 divisors.