The number 47121
47121 is a composite number with 8 divisors. Its prime factorisation is 3 × 113 × 139. Divisors (8): 1, 3, 113, 139, 339, 417, 15707, 47121.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
47121 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
47121 is composite. Its prime factorisation is
- 3
The divisors add up to 63840; without 47121 itself that is 16719, so 47121 is deficient (16719 is less than 47121). Euler's totient φ(47121) = 30912 numbers up to 47121 share no factor with it.
- 4
The digits of 47121 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 101 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47121 = 3 \times 113 \times 139 \]
47121 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 63840 |
| Euler totient φ(n) | 30912 |
| Square | 2220388641 |
| Cube | 104626933152561 |
| Square root | 217.073720 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 101 |
| Scientific notation | 4.7121 × |
47121 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand one hundred and twenty-one |
| Binary (base 2) | 1011100000010001 |
| Octal (base 8) | 134021 |
| Hexadecimal (base 16) | B811 |
| Base 3 | 2101122020 |
| As time | 47121 seconds = 13 h 5 min 21 s |
Is 47121 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 (47121 ÷ 3 = 15707) | 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 | No (remainder 1) | 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 | No (remainder 4) | 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 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 47121 a prime number?
No. 47121 = 3 × 113 × 139, so it is divisible by 3.
What are the factors of 47121?
1, 3, 113, 139, 339, 417, 15707, 47121.
What is 47121 in binary?
1011100000010001 (hexadecimal B811, octal 134021).
What is the square root of 47121?
About 217.0737.
Is 47121 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 47121?
It is a composite number with 8 divisors.