This is a simple C# program to check whether entered number is a prime number or not. If you are a c# beginner or want to start learning the c# programming language, then this program will help you to understand the basics of c# programming. In this program, I will explain how to write a c# program to check prime number.
Copy the below c# program and execute it in your Microsoft Visual Studio IDE (Integrated Development Environment ). At the end of this program, I have shared the output of program this program.
public class PrimeNumberProgram
public static void Main(string args)
int n, i, m=0, flag=0;
Console.Write("Enter any number to check prime number: ");
n = int.Parse(Console.ReadLine());
for(i = 2; i <= m; i++)
if(n % i == 0)
Console.Write("This is not Prime Number.");
Console.Write("This is a prime number.");
Enter any number to check prime number: 11
This is a prime number.