# Kotlin – Find factorial of a number

## Find Factorial of a Number in Kotlin

In this tutorial, you will learn how to calculate the factorial of a given number using Kotlin.

The factorial of a number is the product of all positive integers from 1 to that number. In Kotlin, you can use a loop to calculate the factorial of a given number. This process involves multiplying the current number with the previous result as you iterate through the numbers.

## Example

### Calculate Factorial

We’ll start with an example of calculating the factorial of a number:

Factorial of a number is the product of all positive integers from 1 to that number.

In this example, the `calculateFactorial()` function uses a loop to calculate the factorial of the given number. The result is the product of all positive integers from 1 to the given number.

Kotlin Program

``````// Function to calculate factorial
fun calculateFactorial(number: Int): Long {
var factorial = 1L
for (i in 1..number) {
factorial *= i
}
return factorial
}

fun main() {
val number = 5
val result = calculateFactorial(number)
println("Factorial of \$number is: \$result")
}``````

Output

``Factorial of 5 is: 120``

## Summary

In this Kotlin Tutorial, we learned how to find the factorial of a given number in Kotlin, with the help of example programs.