The number 47942
47942 is a composite number with 4 divisors. Its prime factorisation is 2 × 23971. Divisors (4): 1, 2, 23971, 47942.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 47942: a semiprime: 2 × 23971, the product of two primes.
- 2
47942 is composite. Its prime factorisation is
- 3
The divisors add up to 71916; without 47942 itself that is 23974, so 47942 is deficient (23974 is less than 47942). Euler's totient φ(47942) = 23970 numbers up to 47942 share no factor with it.
- 4
The digits of 47942 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 83 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47942 = 2 \times 23971 \]
47942 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 71916 |
| Euler totient φ(n) | 23970 |
| Square | 2298435364 |
| Cube | 110191588220888 |
| Square root | 218.956617 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 83 |
| Scientific notation | 4.7942 × |
47942 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand nine hundred and forty-two |
| Binary (base 2) | 1011101101000110 |
| Octal (base 8) | 135506 |
| Hexadecimal (base 16) | BB46 |
| Base 3 | 2102202122 |
| As time | 47942 seconds = 13 h 19 min 2 s |
Is 47942 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (47942 ÷ 2 = 23971) | 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 8) | 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 4) | 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 47942 a prime number?
No. 47942 = 2 × 23971, so it is divisible by 2.
What are the factors of 47942?
1, 2, 23971, 47942.
What is 47942 in binary?
1011101101000110 (hexadecimal BB46, octal 135506).
What is the square root of 47942?
About 218.9566.
Is 47942 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 47942?
47942 is a semiprime: 2 × 23971, the product of two primes.