The number 47105
47105 is a composite number with 4 divisors. Its prime factorisation is 5 × 9421. Divisors (4): 1, 5, 9421, 47105.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 47105: a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 5 × 9421, the product of two primes.
- 2
47105 is composite. Its prime factorisation is
- 3
The divisors add up to 56532; without 47105 itself that is 9427, so 47105 is deficient (9427 is less than 47105). Euler's totient φ(47105) = 37680 numbers up to 47105 share no factor with it.
- 4
The digits of 47105 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 57 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47105 = 5 \times 9421 \]
47105 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 56532 |
| Euler totient φ(n) | 37680 |
| Square | 2218881025 |
| Cube | 104520390682625 |
| Square root | 217.036863 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 57 |
| Scientific notation | 4.7105 × |
47105 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand one hundred and five |
| Binary (base 2) | 1011100000000001 |
| Octal (base 8) | 134001 |
| Hexadecimal (base 16) | B801 |
| Base 3 | 2101121122 |
| As time | 47105 seconds = 13 h 5 min 5 s |
Is 47105 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (47105 ÷ 5 = 9421) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 1) | 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 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 47105 a prime number?
No. 47105 = 5 × 9421, so it is divisible by 5.
What are the factors of 47105?
1, 5, 9421, 47105.
What is 47105 in binary?
1011100000000001 (hexadecimal B801, octal 134001).
What is the square root of 47105?
About 217.0369.
Is 47105 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 47105?
47105 is a happy number: repeatedly adding the squares of its digits reaches 1; a semiprime: 5 × 9421, the product of two primes.