The number 42040
42040 is a composite number with 16 divisors. Its prime factorisation is × 5 × 1051. Divisors (16): 1, 2, 4, 5, 8, 10, 20, 40, 1051, 2102, 4204, 5255, 8408, 10510, 21020, 42040.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42040: a Harshad number: divisible by its digit sum 10.
- 2
42040 is composite. Its prime factorisation is
- 3
The divisors add up to 94680; without 42040 itself that is 52640, so 42040 is abundant (52640 is more than 42040). Euler's totient φ(42040) = 16800 numbers up to 42040 share no factor with it.
- 4
The digits of 42040 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 88 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42040 = 2^{3} \times 5 \times 1051 \]42040 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 94680 |
| Euler totient φ(n) | 16800 |
| Square | 1767361600 |
| Cube | 74299881664000 |
| Square root | 205.036582 (= 2√10510) |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 88 |
| Scientific notation | 4.204 × |
42040 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and forty |
| Binary (base 2) | 1010010000111000 |
| Octal (base 8) | 122070 |
| Hexadecimal (base 16) | A438 |
| Base 3 | 2010200001 |
| As time | 42040 seconds = 11 h 40 min 40 s |
Is 42040 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42040 ÷ 2 = 21020) | 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 (42040 ÷ 4 = 10510) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (42040 ÷ 5 = 8408) | 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 | No (remainder 5) | 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 (42040 ÷ 8 = 5255) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (42040 ÷ 10 = 4204) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 42040 a prime number?
No. 42040 = × 5 × 1051, so it is divisible by 2.
What are the factors of 42040?
1, 2, 4, 5, 8, 10, 20, 40, 1051, 2102, 4204, 5255, 8408, 10510, 21020, 42040.
What is 42040 in binary?
1010010000111000 (hexadecimal A438, octal 122070).
What is the square root of 42040?
About 205.0366, exactly 2√10510.
Is 42040 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 42040?
42040 is a Harshad number: divisible by its digit sum 10.