The number 43742
43742 is a composite number with 4 divisors. Its prime factorisation is 2 × 21871. Divisors (4): 1, 2, 21871, 43742.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 43742: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 21871, the product of two primes.
- 2
43742 is composite. Its prime factorisation is
- 3
The divisors add up to 65616; without 43742 itself that is 21874, so 43742 is deficient (21874 is less than 43742). Euler's totient φ(43742) = 21870 numbers up to 43742 share no factor with it.
- 4
The digits of 43742 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 238 steps to reach 1.
LaTeX source of the formulas on this page
\[ 43742 = 2 \times 21871 \]
43742 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 65616 |
| Euler totient φ(n) | 21870 |
| Square | 1913362564 |
| Cube | 83694305274488 |
| Square root | 209.145882 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 238 |
| Scientific notation | 4.3742 × |
43742 in other forms
| Form | Value |
|---|---|
| In words | forty-three thousand seven hundred and forty-two |
| Binary (base 2) | 1010101011011110 |
| Octal (base 8) | 125336 |
| Hexadecimal (base 16) | AADE |
| Base 3 | 2020000002 |
| As time | 43742 seconds = 12 h 9 min 2 s |
Is 43742 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (43742 ÷ 2 = 21871) | 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 6) | 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 2) | 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 6) | 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 43742 a prime number?
No. 43742 = 2 × 21871, so it is divisible by 2.
What are the factors of 43742?
1, 2, 21871, 43742.
What is 43742 in binary?
1010101011011110 (hexadecimal AADE, octal 125336).
What is the square root of 43742?
About 209.1459.
Is 43742 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 43742?
43742 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 2 × 21871, the product of two primes.