#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n, m, ans = 1;
    cin >> n >> m;
    for(;n <= m; n++)
    {
    	int k = sqrt(n);
        if(k * k == n)
        {
            int num = n;
			long long sum = 0;
			while(num != 0)
			{
				sum += num % 10;
				num /= 10;
			}
			bool b = 1;
			if(n <= 1)
			    b = 0;
			for(int i = 2; i <= sqrt(n); i++) 
			{
				if(sum % i == 0)
				{
					b = 0;
					break;
				}
			}
			if(b)
			{
				ans = (ans * n)%998244353;
			}
        }
	}
	cout << ans << endl;
	return 0;
}

理论上是真缺德