The number 18028
18028 is a composite number with 6 divisors. Its prime factorisation is × 4507. Divisors (6): 1, 2, 4, 4507, 9014, 18028.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18028: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
18028 is composite. Its prime factorisation is
- 3
The divisors add up to 31556; without 18028 itself that is 13528, so 18028 is deficient (13528 is less than 18028). Euler's totient φ(18028) = 9012 numbers up to 18028 share no factor with it.
- 4
The digits of 18028 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 92 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18028 = 2^{2} \times 4507 \]18028 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 31556 |
| Euler totient φ(n) | 9012 |
| Square | 325008784 |
| Cube | 5859258357952 |
| Square root | 134.268388 (= 2√4507) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 92 |
| Scientific notation | 1.8028 × |
18028 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand and twenty-eight |
| Binary (base 2) | 100011001101100 |
| Octal (base 8) | 43154 |
| Hexadecimal (base 16) | 466C |
| Base 3 | 220201201 |
| As time | 18028 seconds = 5 h 0 min 28 s |
Is 18028 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (18028 ÷ 2 = 9014) | 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 | Yes (18028 ÷ 4 = 4507) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 1) | 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 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18028 a prime number?
No. 18028 = × 4507, so it is divisible by 2.
What are the factors of 18028?
1, 2, 4, 4507, 9014, 18028.
What is 18028 in binary?
100011001101100 (hexadecimal 466C, octal 43154).
What is the square root of 18028?
About 134.2684, exactly 2√4507.
Is 18028 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 18028?
18028 is a happy number: repeatedly adding the squares of its digits reaches 1.