Full Prime Number Program in Java

Write a program to input an integer from the user, and check if that number is a full prime.

A number is said to be a full prime if it is a prime number and all its digits are also prime numbers.

For example, 23 is a full prime number because 23 itself is prime, and all its digits 2, 3 are also prime.

import java.io.*;
class FullPrime{
    public static void main(String args[])throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter the number: ");
        int num = Integer.parseInt(br.readLine());
        if(isPrime(num)){
            int n = num;
            loop:
            while(n != 0){
                int d = n % 10;
                switch(d){
                    case 2:
                    case 3:
                    case 5:
                    case 7:
                    n /= 10;
                    break;
                    default:
                    break loop;
                }
            }
            if(n == 0)
                System.out.println(num + " is full prime.");
            else
                System.out.println(num + " is not full prime.");
        }
        else
            System.out.println(num + " is not full prime.");
    }
    public static boolean isPrime(int n){
        int f = 0;
        for(int i = 1; i <= n; i++){
            if(n % i == 0)
                f++;
        }
        return f == 2;
    }
}

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