The number 28989
28989 is a composite number with 6 divisors. Its prime factorisation is × 3221. Divisors (6): 1, 3, 9, 3221, 9663, 28989.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
28989 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
28989 is composite. Its prime factorisation is
- 3
The divisors add up to 41886; without 28989 itself that is 12897, so 28989 is deficient (12897 is less than 28989). Euler's totient φ(28989) = 19320 numbers up to 28989 share no factor with it.
- 4
The digits of 28989 add up to 36, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 121 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28989 = 3^{2} \times 3221 \]28989 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 41886 |
| Euler totient φ(n) | 19320 |
| Square | 840362121 |
| Cube | 24361257525669 |
| Square root | 170.261563 (= 3√3221) |
| Digit sum / digital root | 36 / 9 |
| Collatz steps to 1 | 121 |
| Scientific notation | 2.8989 × |
28989 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand nine hundred and eighty-nine |
| Binary (base 2) | 111000100111101 |
| Octal (base 8) | 70475 |
| Hexadecimal (base 16) | 713D |
| Base 3 | 1110202200 |
| As time | 28989 seconds = 8 h 3 min 9 s |
Is 28989 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 | Yes (28989 ÷ 3 = 9663) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | 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 3) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (28989 ÷ 9 = 3221) | 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 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 28989 a prime number?
No. 28989 = × 3221, so it is divisible by 3.
What are the factors of 28989?
1, 3, 9, 3221, 9663, 28989.
What is 28989 in binary?
111000100111101 (hexadecimal 713D, octal 70475).
What is the square root of 28989?
About 170.2616, exactly 3√3221.
Is 28989 divisible by 3?
Yes. Its digits add up to 36, a multiple of 3.
What is special about the number 28989?
It is a composite number with 6 divisors.