#include <iostream>#include <cstring>#include <cstdio>#include <string>#include <algorithm>#include <cmath>#include <vector>using namespace std;#define maxn ( 200000 + 100 )#define maxe ( 800000 + 10 )#define LL long long#define eps 10e-8#define pii pair<int, int>#define MP make_pairLL getans ( LL n ){ LL tn = n, res = n; for( int i = 2; i <= sqrt( n * 1.0 ); ++i ){ if( n % i == 0 ) { res = res / i * ( i - 1 ); while( n % i == 0 ) n /= i; } } if( n > 1 ) res = res / n * ( n - 1 ); return res;}int main (){ LL n; while( ~scanf("%I64d", &n ) && n ) { printf("%I64dn", getans( n )); }}
