The number 47890
47890 is a composite number with 8 divisors. Its prime factorisation is 2 × 5 × 4789. Divisors (8): 1, 2, 5, 10, 4789, 9578, 23945, 47890.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
47890 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
47890 is composite. Its prime factorisation is
- 3
The divisors add up to 86220; without 47890 itself that is 38330, so 47890 is deficient (38330 is less than 47890). Euler's totient φ(47890) = 19152 numbers up to 47890 share no factor with it.
- 4
The digits of 47890 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 96 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47890 = 2 \times 5 \times 4789 \]
47890 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 86220 |
| Euler totient φ(n) | 19152 |
| Square | 2293452100 |
| Cube | 109833421069000 |
| Square root | 218.837840 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 96 |
| Scientific notation | 4.789 × |
47890 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand eight hundred and ninety |
| Binary (base 2) | 1011101100010010 |
| Octal (base 8) | 135422 |
| Hexadecimal (base 16) | BB12 |
| Base 3 | 2102200201 |
| As time | 47890 seconds = 13 h 18 min 10 s |
Is 47890 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (47890 ÷ 2 = 23945) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | 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 | Yes (47890 ÷ 5 = 9578) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (47890 ÷ 10 = 4789) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 47890 a prime number?
No. 47890 = 2 × 5 × 4789, so it is divisible by 2.
What are the factors of 47890?
1, 2, 5, 10, 4789, 9578, 23945, 47890.
What is 47890 in binary?
1011101100010010 (hexadecimal BB12, octal 135422).
What is the square root of 47890?
About 218.8378.
Is 47890 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 47890?
It is a composite number with 8 divisors.