The number 42168
42168 is a composite number with 32 divisors. Its prime factorisation is × 3 × 7 × 251. Divisors (32): 1, 2, 3, 4, 6, 7, 8, 12, 14, 21, 24, 28, 42, 56, 84, 168 … 42168.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42168: a Harshad number: divisible by its digit sum 21.
- 2
42168 is composite. Its prime factorisation is
- 3
The divisors add up to 120960; without 42168 itself that is 78792, so 42168 is abundant (78792 is more than 42168). Euler's totient φ(42168) = 12000 numbers up to 42168 share no factor with it.
- 4
The digits of 42168 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42168 = 2^{3} \times 3 \times 7 \times 251 \]42168 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 120960 |
| Euler totient φ(n) | 12000 |
| Square | 1778140224 |
| Cube | 74980616965632 |
| Square root | 205.348484 (= 2√10542) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 57 |
| Scientific notation | 4.2168 × |
42168 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand one hundred and sixty-eight |
| Binary (base 2) | 1010010010111000 |
| Octal (base 8) | 122270 |
| Hexadecimal (base 16) | A4B8 |
| Base 3 | 2010211210 |
| As time | 42168 seconds = 11 h 42 min 48 s |
Is 42168 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42168 ÷ 2 = 21084) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (42168 ÷ 3 = 14056) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (42168 ÷ 4 = 10542) | 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 | Yes (42168 ÷ 6 = 7028) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (42168 ÷ 7 = 6024) | 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 (42168 ÷ 8 = 5271) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (42168 ÷ 12 = 3514) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42168 a prime number?
No. 42168 = × 3 × 7 × 251, so it is divisible by 2.
What are the factors of 42168?
1, 2, 3, 4, 6, 7, 8, 12, 14, 21, 24, 28, 42, 56, 84, 168, 251, 502, 753, 1004, 1506, 1757, 2008, 3012, 3514, 5271, 6024, 7028, 10542, 14056, 21084, 42168.
What is 42168 in binary?
1010010010111000 (hexadecimal A4B8, octal 122270).
What is the square root of 42168?
About 205.3485, exactly 2√10542.
Is 42168 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 42168?
42168 is a Harshad number: divisible by its digit sum 21.