#include <stdio.h>

#define MAXLEN 20

unsigned long long p10[MAXLEN];

#define MAXNUM 100000000
int nprimes;
int primes[MAXNUM];

void getprimes()
{
	primes[0] = 2;
	nprimes = 1;
	for (int i = 3; i <= MAXNUM; i+=2) {
		int isprime = 1;
		for (int j = 0; j < nprimes; j++) {
			if (primes[j] * primes[j] > i)
				break;
			if (i % primes[j] == 0) {
				isprime = 0;
				break;
			}
		}
		if (isprime) {
			primes[nprimes] = i;
			nprimes ++;
		}
	}
}

void init()
{
	int i;

	p10[0] = 1;
	for (i = 1; i < MAXLEN; i++)
		p10[i] = p10[i-1] * 10;
	getprimes();
}

int isprime(unsigned long long x)
{
	for (int i = 0; primes[i] * primes[i] <= x; i++) {
		if (x % primes[i] == 0)
			return 0;
	}
	return 1;
}

static int getdigits(unsigned long long x, int d[])
{
	int nd = 0;
	while (x > 0) {
		d[nd] = x % 10;
		nd++;
		x /= 10;
	}
	return nd;
}

/* the number of digits to be replaced must be multiple of 3,
 * otherwise at least 3 of the replaced numbers are multiple of 3
 */
int search3(unsigned long long x)
{
	int digits[40];
	int nd;
	int i, j, k;
	unsigned long long t;

	nd = getdigits(x, digits);

	for (i = 0; i < nd-2; i++) {
		if (digits[i] >= 3) /* at most 7 numbers */
			continue;
		for (j = i+1; j < nd-1; j++) {
			if (digits[j] != digits[i])
				continue;
			for (k = j+1; k < nd; k++) {
				if (digits[k] != digits[i])
					continue;
				unsigned long long delta = p10[i] + p10[j] + p10[k];
				int cnt = 1; /* assume x is prime */
				t = x;
				int tmp = digits[i] + 1;
				while (tmp < 10) {
					t += delta;
					if (isprime(t))
						cnt++;

					tmp++;
				}
				if (cnt >= 8)
					return 1;
			}
		}
	}
	return 0;
}

int main()
{
	unsigned long long t = 1001;
	init();
	while (1) {
		if (isprime(t) && search3(t)) {
			printf("%lld\n", t);
			return 0;
		}
		t += 2;
	}
}