import java.util.*;

public class Euler49 {
    private static boolean runCheckpoints = true;

    private static boolean parseArguments(String[] args) {
        for (int i = 0; i < args.length; ++i) {
            String arg = args[i];
            if (arg.equals("--skip-checkpoints")) {
                runCheckpoints = false;
                continue;
            }
            System.err.println("Unknown argument: " + arg);
            return false;
        }
        return true;
    }

    private static boolean isPrime(int n) {
        if (n < 2) {
            return false;
        }
        if ((n % 2) == 0) {
            return n == 2;
        }
        for (int p = 3; p <= n / p; p += 2) {
            if ((n % p) == 0) {
                return false;
            }
        }
        return true;
    }

    private static String sortedDigits(int n) {
        char[] chars = String.valueOf(n).toCharArray();
        Arrays.sort(chars);
        return new String(chars);
    }

    private static long solve() {
        Map<String, List<Integer>> groups = new HashMap<>();

        for (int p = 1000; p < 10000; ++p) {
            if (isPrime(p)) {
                String key = sortedDigits(p);
                groups.computeIfAbsent(key, k -> new ArrayList<>()).add(p);
            }
        }

        for (Map.Entry<String, List<Integer>> entry : groups.entrySet()) {
            List<Integer> values = entry.getValue();
            if (values.size() < 3) {
                continue;
            }

            Collections.sort(values);

            for (int i = 0; i < values.size(); ++i) {
                for (int j = i + 1; j < values.size(); ++j) {
                    int a = values.get(i);
                    int b = values.get(j);
                    int c = 2 * b - a;

                    if (c > 9999) {
                        continue;
                    }
                    if (Collections.binarySearch(values, c) < 0) {
                        continue;
                    }
                    if (a == 1487 && b == 4817) {
                        continue;
                    }

                    return Long.parseLong(String.valueOf(a) + String.valueOf(b) + String.valueOf(c));
                }
            }
        }

        return 0L;
    }

    private static boolean runCheckpoints() {
        if (!isPrime(1487) || !isPrime(4817) || !isPrime(8147)) {
            System.err.println("Checkpoint failed for example primes");
            return false;
        }
        String sd1 = sortedDigits(1487);
        if (!sd1.equals(sortedDigits(4817)) || !sd1.equals(sortedDigits(8147))) {
            System.err.println("Checkpoint failed for permutation grouping");
            return false;
        }
        return true;
    }

    public static void main(String[] args) {
        if (!parseArguments(args)) {
            System.exit(1);
        }
        if (runCheckpoints && !runCheckpoints()) {
            System.exit(2);
        }

        System.out.println(solve());
    }
}