The number 9998
9998 is a composite number with 4 divisors. Its prime factorisation is 2 × 4999. Divisors (4): 1, 2, 4999, 9998.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 9998: a semiprime: 2 × 4999, the product of two primes.
- 2
9998 is composite. Its prime factorisation is
- 3
The divisors add up to 15000; without 9998 itself that is 5002, so 9998 is deficient (5002 is less than 9998). Euler's totient φ(9998) = 4998 numbers up to 9998 share no factor with it.
- 4
The digits of 9998 add up to 35, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 91 steps to reach 1.
LaTeX source of the formulas on this page
\[ 9998 = 2 \times 4999 \]
9998 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 15000 |
| Euler totient φ(n) | 4998 |
| Square | 99960004 |
| Cube | 999400119992 |
| Square root | 99.989999 |
| Digit sum / digital root | 35 / 8 |
| Collatz steps to 1 | 91 |
| Scientific notation | 9.998 × |
9998 in other forms
| Form | Value |
|---|---|
| In words | nine thousand nine hundred and ninety-eight |
| Binary (base 2) | 10011100001110 |
| Octal (base 8) | 23416 |
| Hexadecimal (base 16) | 270E |
| Base 3 | 111201022 |
| As time | 9998 seconds = 2 h 46 min 38 s |
Is 9998 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (9998 ÷ 2 = 4999) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 9998 a prime number?
No. 9998 = 2 × 4999, so it is divisible by 2.
What are the factors of 9998?
1, 2, 4999, 9998.
What is 9998 in binary?
10011100001110 (hexadecimal 270E, octal 23416).
What is the square root of 9998?
About 99.9900.
Is 9998 divisible by 3?
No. Its digits add up to 35, which is not a multiple of 3.
What is special about the number 9998?
9998 is a semiprime: 2 × 4999, the product of two primes.