1. Java program to check whether a number is prime or not

class prime
{
public static void main(String...s)
{
int n,i;
n=Integer.parseInt(s[0]);

for(i=2;i<n;++i)
{
if(n%i==0)
break;
}

if(i==n)
System.out.println("\nNumber is prime");
else
System.out.println("\nNumber is not prime");
}
}

2. Java program to find sum of digits of a number

class sum
{
public static void main(String...s)
{
int n,i,sum=0;
n=Integer.parseInt(s[0]);

while(n!=0)
{
i=n%10;
sum+=i;
n/=10;
}

System.out.println(sum);
}
}

3. Java program to find whether a number is armstrong or not

class Armstrong
{
public static void main(String...s)
{
int m,n,i,j=0;
n=Integer.parseInt(s[0]);

m=n;
while(n!=0)
{
i=n%10;
j+=(i*i*i);
n/=10;
}

if(j==m)
System.out.println("\nNumber is armstrong");
else
System.out.println("\nNumber is not armstrong");
}
}

4. Java program to display multiplication table of any number

class Table
{
public static void main(String...s)
{
int n,i;
n=Integer.parseInt(s[0]);

for(i=1;i<=10;++i)
System.out.println(n+" * "+i+" = "+(n*i));
}
}

5. Java program to check whether a given number is palindrome or not

class Palindrome
{
public static void main(String...s)
{
int n,m,rev=0,i;
n=Integer.parseInt(s[0]);
m=n;

while(n!=0)
{
i=n%10;
rev=(rev*10)+i;
n/=10;
}

if(m==rev)
System.out.println("\nNumber is 

palindrome");
else
System.out.println("\nNumber is not 

palindrome");
}
}

6. Java program to find factorial of given number

class Factorial
{
public static void main(String...s)
{
int n,fac=1,i;
n=Integer.parseInt(s[0]);

for(i=1;i<=n;i++)
fac*=i;

System.out.println("\nFactorial="+fac);
}
}

7. Java program to reverse a given number

class Reverse
{
public static void main(String...s)
{
int n,rev=0,i;
n=Integer.parseInt(s[0]);

while(n!=0)
{
i=n%10;
rev=(rev*10)+i;
n/=10;
}

System.out.println("\nReverse="+rev);
}
}

8. Java program to print fibonacci series

class Fibonacci
{
public static void main(String...s)
{
int first=0,second=1,third,n,i;
n=Integer.parseInt(s[0]);

System.out.print("\n"+first+" "+second);
for(i=2;i<n;i++)
{
third=first+second;
first=second;
second=third;
System.out.print(" "+third);
}
System.out.println();
}
}