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Kotlin program to check whether a number is prime or not

Kotlin | Check prime number: Here, we are going to learn how to check whether a given number is prime or not in Kotlin programming language?
Submitted by IncludeHelp, on April 24, 2020

A prime number is a natural number that is greater than 1 and cannot be formed by multiplying two smaller natural numbers.

Given a number num, we have to check whether num is a prime number or not.

Example:

    Input:
    num = 83

    Output:
    83 is a Prime Number

Program to check whether a number is prime or not in Kotlin

/**
 * Kotlin program to check given number is Prime Number or Not
*/

package com.includehelp.basic

import java.util.*


//Function to check Prime Number
fun isPrimeNo(number: Int): Boolean {
    if(number<2) return false
    for (i in 2..number/2) {
        if (number % i == 0) {
            return false
        }
    }
    return true
}

//Main Function, Entry Point of Program
fun main(arg: Array<String>) {
    val sc = Scanner(System.`in`)

    //Input Number
    println("Enter Number  : ")
    val num: Int = sc.nextInt()

    //Call Function to Check Prime Number
    if (isPrimeNo(num)) {
        println("$num is a Prime Number")
    } else {
        println("$num is not a Prime Number")
    }
}

Output

RUN 1:
Enter Number  :
83
83 is a Prime Number
---
RUN 2:
Enter Number  :
279
279 is not a Prime Number
---
RUN 3:
Enter Number  :
29
29 is a Prime Number