The number 28490
28490 is a composite number with 32 divisors. Its prime factorisation is 2 × 5 × 7 × 11 × 37. Divisors (32): 1, 2, 5, 7, 10, 11, 14, 22, 35, 37, 55, 70, 74, 77, 110, 154 … 28490.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
28490 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
28490 is composite. Its prime factorisation is
- 3
The divisors add up to 65664; without 28490 itself that is 37174, so 28490 is abundant (37174 is more than 28490). Euler's totient φ(28490) = 8640 numbers up to 28490 share no factor with it.
- 4
The digits of 28490 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 51 steps to reach 1.
LaTeX source of the formulas on this page
\[ 28490 = 2 \times 5 \times 7 \times 11 \times 37 \]
28490 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 65664 |
| Euler totient φ(n) | 8640 |
| Square | 811680100 |
| Cube | 23124766049000 |
| Square root | 168.789810 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 51 |
| Scientific notation | 2.849 × |
28490 in other forms
| Form | Value |
|---|---|
| In words | twenty-eight thousand four hundred and ninety |
| Binary (base 2) | 110111101001010 |
| Octal (base 8) | 67512 |
| Hexadecimal (base 16) | 6F4A |
| Base 3 | 1110002012 |
| As time | 28490 seconds = 7 h 54 min 50 s |
Is 28490 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (28490 ÷ 2 = 14245) | 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 | Yes (28490 ÷ 5 = 5698) | 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 | Yes (28490 ÷ 7 = 4070) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (28490 ÷ 10 = 2849) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (28490 ÷ 11 = 2590) | 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 28490 a prime number?
No. 28490 = 2 × 5 × 7 × 11 × 37, so it is divisible by 2.
What are the factors of 28490?
1, 2, 5, 7, 10, 11, 14, 22, 35, 37, 55, 70, 74, 77, 110, 154, 185, 259, 370, 385, 407, 518, 770, 814, 1295, 2035, 2590, 2849, 4070, 5698, 14245, 28490.
What is 28490 in binary?
110111101001010 (hexadecimal 6F4A, octal 67512).
What is the square root of 28490?
About 168.7898.
Is 28490 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 28490?
It is a composite number with 32 divisors.