The number 18390
18390 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 5 × 613. Divisors (16): 1, 2, 3, 5, 6, 10, 15, 30, 613, 1226, 1839, 3065, 3678, 6130, 9195, 18390.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
18390 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
18390 is composite. Its prime factorisation is
- 3
The divisors add up to 44208; without 18390 itself that is 25818, so 18390 is abundant (25818 is more than 18390). Euler's totient φ(18390) = 4896 numbers up to 18390 share no factor with it.
- 4
The digits of 18390 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 154 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18390 = 2 \times 3 \times 5 \times 613 \]
18390 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 44208 |
| Euler totient φ(n) | 4896 |
| Square | 338192100 |
| Cube | 6219352719000 |
| Square root | 135.609734 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 154 |
| Scientific notation | 1.839 × |
18390 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand three hundred and ninety |
| Binary (base 2) | 100011111010110 |
| Octal (base 8) | 43726 |
| Hexadecimal (base 16) | 47D6 |
| Base 3 | 221020010 |
| As time | 18390 seconds = 5 h 6 min 30 s |
Is 18390 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (18390 ÷ 2 = 9195) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (18390 ÷ 3 = 6130) | 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 (18390 ÷ 5 = 3678) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (18390 ÷ 6 = 3065) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (18390 ÷ 10 = 1839) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 18390 a prime number?
No. 18390 = 2 × 3 × 5 × 613, so it is divisible by 2.
What are the factors of 18390?
1, 2, 3, 5, 6, 10, 15, 30, 613, 1226, 1839, 3065, 3678, 6130, 9195, 18390.
What is 18390 in binary?
100011111010110 (hexadecimal 47D6, octal 43726).
What is the square root of 18390?
About 135.6097.
Is 18390 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 18390?
It is a composite number with 16 divisors.