Emirp number - Java Program
20-07-2018    3588 times

### Emirp number - Java Program

An Emirp number is a number which is prime backwards and forwards. Now write a program to check a number is Emirp number or not.

If we write the word "prime" backward, then it generate a word called "Emirp". Emirp number is refers to a prime number that becomes a prime number when we reverse its digits. but the palindrom prime numbers are not included as Emirps(like 151 or 787) nor 1-digit primes like 7.

Example: 13 is an Emirp number since 13 and 31 are both prime numbers. Some others examples are 17, 107, 113, 149, and 157

import java.util.*;
public class Emirp
{
public boolean IsPrime(int i)
{
boolean b=true;
int d=2;
while(d<i/2)
{
if (i%d==0)
{
b=false;
break;
}
d++;
}
return b;
}
public static void main(String []args)
{
int i,r1=3,r2=100;
Emirp ep=new Emirp();
Scanner sc=new Scanner(System.in);
System.out.print("Enter A Number : ");
int no=sc.nextInt();
int fr=no;
int rev=0;
while(no>0)
{
rev = (rev*10) + (no%10);
no /= 10;
}
if(ep.IsPrime(fr) && ep.IsPrime(rev))
{
System.out.print(fr + " is a Emirp Number");
}
else
{
System.out.print(fr + " is not a Emirp Number");
}
}
}


Enter A Number : 17

17 is a Emirp Number

Enter A Number : 51

51 is not a Emirp Number