The number 47775
47775 is a composite number with 36 divisors. Its prime factorisation is 3 × × × 13. Divisors (36): 1, 3, 5, 7, 13, 15, 21, 25, 35, 39, 49, 65, 75, 91, 105, 147 … 47775.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 47775: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
47775 is composite. Its prime factorisation is
- 3
The divisors add up to 98952; without 47775 itself that is 51177, so 47775 is abundant (51177 is more than 47775). Euler's totient φ(47775) = 20160 numbers up to 47775 share no factor with it.
- 4
The digits of 47775 add up to 30, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 101 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47775 = 3 \times 5^{2} \times 7^{2} \times 13 \]47775 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 36 |
| Sum of divisors | 98952 |
| Euler totient φ(n) | 20160 |
| Square | 2282450625 |
| Cube | 109044078609375 |
| Square root | 218.574930 (= 35√39) |
| Digit sum / digital root | 30 / 3 |
| Collatz steps to 1 | 101 |
| Scientific notation | 4.7775 × |
47775 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand seven hundred and seventy-five |
| Binary (base 2) | 1011101010011111 |
| Octal (base 8) | 135237 |
| Hexadecimal (base 16) | BA9F |
| Base 3 | 2102112110 |
| As time | 47775 seconds = 13 h 16 min 15 s |
Is 47775 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 | Yes (47775 ÷ 3 = 15925) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (47775 ÷ 5 = 9555) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (47775 ÷ 7 = 6825) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | 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 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 47775 a prime number?
No. 47775 = 3 × × × 13, so it is divisible by 3.
What are the factors of 47775?
1, 3, 5, 7, 13, 15, 21, 25, 35, 39, 49, 65, 75, 91, 105, 147, 175, 195, 245, 273, 325, 455, 525, 637, 735, 975, 1225, 1365, 1911, 2275, 3185, 3675, 6825, 9555, 15925, 47775.
What is 47775 in binary?
1011101010011111 (hexadecimal BA9F, octal 135237).
What is the square root of 47775?
About 218.5749, exactly 35√39.
Is 47775 divisible by 3?
Yes. Its digits add up to 30, a multiple of 3.
What is special about the number 47775?
47775 is a happy number: repeatedly adding the squares of its digits reaches 1.