#include <cstring>
#include <iostream>
#include <algorithm>
#include <cstdio>
using namespace std;
typedef long long LL;
LL qmul(LL a,LL k,LL b){
LL res = 0;
while(k){
if(k & 1) res = (res + a) % b;
a = (a + a) % b;
k >>= 1;
}
return res;
}
LL qmi(LL a,LL k,LL b){
LL res = 1 % b;
while(k){
if(k & 1) res = qmul(res,a,b);
a = qmul(a,a,b);
k >>= 1;
}
return res;
}
LL get_euler(LL C){
LL res = C;
for(LL i = 2; i <= C / i; i ++){
if(C % i == 0){
while(C % i == 0) C /= i;
res = res / i * (i - 1) ;//防止溢出先除后乘
}
}
if(C > 1) res = res / C * (C - 1);
return res;
}
int main(){
int T = 1;
LL L;
while(cin >> L,L){
int d = 1;
while(L % (d * 2) == 0 && d * 2 <= 8)d *= 2;
LL C = 9 * L / d;
LL phi = get_euler(C);
LL res = 1e18;
if(C % 2 == 0 || C % 5 == 0)res = 0;
for(LL d = 1; d * d <= phi; d ++)
if(phi % d == 0)
{
if(qmi(10,d,C) == 1)res = min(res,d);
if(qmi(10,phi / d,C) == 1)res = min(res,phi / d);
}
printf("Case %d: %lld\n",T ++,res);
}
return 0;
}