The number 9875
9875 is a composite number with 8 divisors. Its prime factorisation is Ć 79. Divisors (8): 1, 5, 25, 79, 125, 395, 1975, 9875.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 9875: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
9875 is composite. Its prime factorisation is
- 3
The divisors add up to 12480; without 9875 itself that is 2605, so 9875 is deficient (2605 is less than 9875). Euler's totient Ļ(9875) = 7800 numbers up to 9875 share no factor with it.
- 4
The digits of 9875 add up to 29, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 135 steps to reach 1.
LaTeX source of the formulas on this page
\[ 9875 = 5^{3} \times 79 \]9875 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 12480 |
| Euler totient Ļ(n) | 7800 |
| Square | 97515625 |
| Cube | 962966796875 |
| Square root | 99.373035 (= 5ā395) |
| Digit sum / digital root | 29 / 2 |
| Collatz steps to 1 | 135 |
| Scientific notation | 9.875 Ć |
9875 in other forms
| Form | Value |
|---|---|
| In words | nine thousand eight hundred and seventy-five |
| Binary (base 2) | 10011010010011 |
| Octal (base 8) | 23223 |
| Hexadecimal (base 16) | 2693 |
| Base 3 | 111112202 |
| As time | 9875 seconds = 2 h 44 min 35 s |
Is 9875 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (9875 Ć· 5 = 1975) | 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 5) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | 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 8) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 9875 a prime number?
No. 9875 = Ć 79, so it is divisible by 5.
What are the factors of 9875?
1, 5, 25, 79, 125, 395, 1975, 9875.
What is 9875 in binary?
10011010010011 (hexadecimal 2693, octal 23223).
What is the square root of 9875?
About 99.3730, exactly 5ā395.
Is 9875 divisible by 3?
No. Its digits add up to 29, which is not a multiple of 3.
What is special about the number 9875?
9875 is a happy number: repeatedly adding the squares of its digits reaches 1.