Go Language - Program to Check Whether a Number is Prime or Not

• Prime numbers are natural numbers that are only divisible by 1 and the number itself.
• A prime number cannot be divided by any other numbers without leaving a remainder.
• An example of a prime number is 17. It can only be divided by 1 and 17, which has only two factors 1 and 5.
• Let's take another example of the number 6, which has more than two factors, i.e 1, 2, 3, and 6. This means 6 is not a prime number.

Example 1. Go Program to check whether the given number is Prime or not

`package mainimport (    "fmt")func main() {    CheckPrimeNumber(11)    CheckPrimeNumber(1)    CheckPrimeNumber(23)    CheckPrimeNumber(20)    CheckPrimeNumber(-9)}func CheckPrimeNumber(number int) {    isPrime := true    if number < 0 {        fmt.Println("Number must be greater than 0")    } else if number == 0 || number == 1 {        fmt.Println(number, "is not a  prime number")    } else {        for i := 2; i <= number/2; i++ {            if number%i == 0 {                fmt.Println(number, " is not a  prime number")                isPrime = false                break            }        }        if isPrime == true {            fmt.Println(number, "is a prime number")        }    }}`

Example 2. Go Program to check whether the number from standard input is Prime or not

`package mainimport (    "fmt")func main() {    var number int    fmt.Println("Enter an integer value : ")    _, err := fmt.Scanf("%d", &number)    if err != nil {        fmt.Println(err)    }    CheckPrimeNumber(number)}func CheckPrimeNumber(number int) {    isPrime := true    if number < 0 {        fmt.Println("Number must be greater than 0")    } else if number == 0 || number == 1 {        fmt.Println(number, "is not a  prime number")    } else {        for i := 2; i <= number/2; i++ {            if number%i == 0 {                fmt.Println(number, " is not a  prime number")                isPrime = false                break            }        }        if isPrime == true {            fmt.Println(number, "is a prime number")        }    }}`