The number 42740
42740 is a composite number with 12 divisors. Its prime factorisation is × 5 × 2137. Divisors (12): 1, 2, 4, 5, 10, 20, 2137, 4274, 8548, 10685, 21370, 42740.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
42740 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
42740 is composite. Its prime factorisation is
- 3
The divisors add up to 89796; without 42740 itself that is 47056, so 42740 is abundant (47056 is more than 42740). Euler's totient φ(42740) = 17088 numbers up to 42740 share no factor with it.
- 4
The digits of 42740 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 49 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42740 = 2^{2} \times 5 \times 2137 \]42740 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 89796 |
| Euler totient φ(n) | 17088 |
| Square | 1826707600 |
| Cube | 78073482824000 |
| Square root | 206.736547 (= 2√10685) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 49 |
| Scientific notation | 4.274 × |
42740 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand seven hundred and forty |
| Binary (base 2) | 1010011011110100 |
| Octal (base 8) | 123364 |
| Hexadecimal (base 16) | A6F4 |
| Base 3 | 2011121222 |
| As time | 42740 seconds = 11 h 52 min 20 s |
Is 42740 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (42740 ÷ 2 = 21370) | 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 | Yes (42740 ÷ 4 = 10685) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (42740 ÷ 5 = 8548) | 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 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 | No (remainder 4) | 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 | Yes (42740 ÷ 10 = 4274) | 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 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42740 a prime number?
No. 42740 = × 5 × 2137, so it is divisible by 2.
What are the factors of 42740?
1, 2, 4, 5, 10, 20, 2137, 4274, 8548, 10685, 21370, 42740.
What is 42740 in binary?
1010011011110100 (hexadecimal A6F4, octal 123364).
What is the square root of 42740?
About 206.7365, exactly 2√10685.
Is 42740 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 42740?
It is a composite number with 12 divisors.