The number 9979
9979 is a composite number with 4 divisors. Its prime factorisation is 17 × 587. Divisors (4): 1, 17, 587, 9979.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 9979: a semiprime: 17 × 587, the product of two primes.
- 2
9979 is composite. Its prime factorisation is
- 3
The divisors add up to 10584; without 9979 itself that is 605, so 9979 is deficient (605 is less than 9979). Euler's totient φ(9979) = 9376 numbers up to 9979 share no factor with it.
- 4
The digits of 9979 add up to 34, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 73 steps to reach 1.
LaTeX source of the formulas on this page
\[ 9979 = 17 \times 587 \]
9979 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 10584 |
| Euler totient φ(n) | 9376 |
| Square | 99580441 |
| Cube | 993713220739 |
| Square root | 99.894945 |
| Digit sum / digital root | 34 / 7 |
| Collatz steps to 1 | 73 |
| Scientific notation | 9.979 × |
9979 in other forms
| Form | Value |
|---|---|
| In words | nine thousand nine hundred and seventy-nine |
| Binary (base 2) | 10011011111011 |
| Octal (base 8) | 23373 |
| Hexadecimal (base 16) | 26FB |
| Base 3 | 111200121 |
| As time | 9979 seconds = 2 h 46 min 19 s |
Is 9979 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 1) | 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 | No (remainder 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 9979 a prime number?
No. 9979 = 17 × 587, so it is divisible by 17.
What are the factors of 9979?
1, 17, 587, 9979.
What is 9979 in binary?
10011011111011 (hexadecimal 26FB, octal 23373).
What is the square root of 9979?
About 99.8949.
Is 9979 divisible by 3?
No. Its digits add up to 34, which is not a multiple of 3.
What is special about the number 9979?
9979 is a semiprime: 17 × 587, the product of two primes.