The number 9820
9820 is a composite number with 12 divisors. Its prime factorisation is × 5 × 491. Divisors (12): 1, 2, 4, 5, 10, 20, 491, 982, 1964, 2455, 4910, 9820.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
9820 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
9820 is composite. Its prime factorisation is
- 3
The divisors add up to 20664; without 9820 itself that is 10844, so 9820 is abundant (10844 is more than 9820). Euler's totient φ(9820) = 3920 numbers up to 9820 share no factor with it.
- 4
The digits of 9820 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 135 steps to reach 1.
LaTeX source of the formulas on this page
\[ 9820 = 2^{2} \times 5 \times 491 \]9820 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 20664 |
| Euler totient φ(n) | 3920 |
| Square | 96432400 |
| Cube | 946966168000 |
| Square root | 99.095913 (= 2√2455) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 135 |
| Scientific notation | 9.82 × |
9820 in other forms
| Form | Value |
|---|---|
| In words | nine thousand eight hundred and twenty |
| Binary (base 2) | 10011001011100 |
| Octal (base 8) | 23134 |
| Hexadecimal (base 16) | 265C |
| Base 3 | 111110201 |
| As time | 9820 seconds = 2 h 43 min 40 s |
Is 9820 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (9820 ÷ 2 = 4910) | 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 | Yes (9820 ÷ 4 = 2455) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (9820 ÷ 5 = 1964) | 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 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 4) | 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 (9820 ÷ 10 = 982) | 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 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 9820 a prime number?
No. 9820 = × 5 × 491, so it is divisible by 2.
What are the factors of 9820?
1, 2, 4, 5, 10, 20, 491, 982, 1964, 2455, 4910, 9820.
What is 9820 in binary?
10011001011100 (hexadecimal 265C, octal 23134).
What is the square root of 9820?
About 99.0959, exactly 2√2455.
Is 9820 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 9820?
It is a composite number with 12 divisors.