The number 28988
28988 is a composite number with 6 divisors. Its prime factorisation is × 7247. Divisors (6): 1, 2, 4, 7247, 14494, 28988.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
28988 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
28988 is composite. Its prime factorisation is
- 3
The divisors add up to 50736; without 28988 itself that is 21748, so 28988 is deficient (21748 is less than 28988). Euler's totient φ(28988) = 14492 numbers up to 28988 share no factor with it.
- 4
The digits of 28988 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 121 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28988 = 2^{2} \times 7247 \]28988 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 50736 |
| Euler totient φ(n) | 14492 |
| Square | 840304144 |
| Cube | 24358736526272 |
| Square root | 170.258627 (= 2√7247) |
| Digit sum / digital root | 35 / 8 |
| Collatz steps to 1 | 121 |
| Scientific notation | 2.8988 × |
28988 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand nine hundred and eighty-eight |
| Binary (base 2) | 111000100111100 |
| Octal (base 8) | 70474 |
| Hexadecimal (base 16) | 713C |
| Base 3 | 1110202122 |
| As time | 28988 seconds = 8 h 3 min 8 s |
Is 28988 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28988 ÷ 2 = 14494) | 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 | Yes (28988 ÷ 4 = 7247) | 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 1) | 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 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28988 a prime number?
No. 28988 = × 7247, so it is divisible by 2.
What are the factors of 28988?
1, 2, 4, 7247, 14494, 28988.
What is 28988 in binary?
111000100111100 (hexadecimal 713C, octal 70474).
What is the square root of 28988?
About 170.2586, exactly 2√7247.
Is 28988 divisible by 3?
No. Its digits add up to 35, which is not a multiple of 3.
What is special about the number 28988?
It is a composite number with 6 divisors.