# Kotlin Function: Check Prime Number, Return Boolean

## Kotlin Function: Exercise-17 with Solution

Write a Kotlin function that takes an integer as an argument and returns a Boolean indicating whether the number is prime or not. Use explicit return type.

**Sample Solution:**

**Kotlin Code:**

```
fun isPrime(number: Int): Boolean {
if (number <= 1) {
return false
}
for (i in 2 until number) {
if (number % i == 0) {
return false
}
}
return true
}
fun main() {
val number = 13
val isNumberPrime = isPrime(number)
println("Is $number a prime number? $isNumberPrime")
}
```

Sample Output:

Is 13 a prime number? True

**Explanation:**

In the above exercise -

- The "isPrime()" function, receives a number parameter of type Int.
- Check if the number is less than or equal to 1, in which case it's not prime, and return false.
- Then, iterate from 2 to one less than the number and check if any number divides the given number without leaving a remainder.
- If find such a divisor, return false, indicating that the number is not prime.
- If the loop ends without finding any divisors, return true, indicating that the number is prime.
- In the "main()" function, we call the "isPrime()" function with a sample number (in this case, 13) and store the result in isNumberPrime. Finally, we print whether the number is prime or not using println.

**Kotlin Editor: **

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