The number 7998
7998 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 31 × 43. Divisors (16): 1, 2, 3, 6, 31, 43, 62, 86, 93, 129, 186, 258, 1333, 2666, 3999, 7998.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
7998 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
7998 is composite. Its prime factorisation is
- 3
The divisors add up to 16896; without 7998 itself that is 8898, so 7998 is abundant (8898 is more than 7998). Euler's totient φ(7998) = 2520 numbers up to 7998 share no factor with it.
- 4
The digits of 7998 add up to 33, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 189 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7998 = 2 \times 3 \times 31 \times 43 \]
7998 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 16896 |
| Euler totient φ(n) | 2520 |
| Square | 63968004 |
| Cube | 511616095992 |
| Square root | 89.431538 |
| Digit sum / digital root | 33 / 6 |
| Collatz steps to 1 | 189 |
| Scientific notation | 7.998 × |
7998 in other forms
| Form | Value |
|---|---|
| In words | seven thousand nine hundred and ninety-eight |
| Binary (base 2) | 1111100111110 |
| Octal (base 8) | 17476 |
| Hexadecimal (base 16) | 1F3E |
| Base 3 | 101222020 |
| As time | 7998 seconds = 2 h 13 min 18 s |
Is 7998 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (7998 ÷ 2 = 3999) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (7998 ÷ 3 = 2666) | 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 | Yes (7998 ÷ 6 = 1333) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 7998 a prime number?
No. 7998 = 2 × 3 × 31 × 43, so it is divisible by 2.
What are the factors of 7998?
1, 2, 3, 6, 31, 43, 62, 86, 93, 129, 186, 258, 1333, 2666, 3999, 7998.
What is 7998 in binary?
1111100111110 (hexadecimal 1F3E, octal 17476).
What is the square root of 7998?
About 89.4315.
Is 7998 divisible by 3?
Yes. Its digits add up to 33, a multiple of 3.
What is special about the number 7998?
It is a composite number with 16 divisors.