#include #include #include int main(void) { unsigned long long int i = 0; unsigned long int j = 0; unsigned char is_prime = 1; unsigned long long int n = 0; unsigned char fact_time = 0; scanf("%lld", &n); i = 1; while ( fact_time <= 2 ) { if ( n == 1 ) { break; } is_prime = 1; for ( i=(i+1); i<=sqrt(n); i++ ) { if ( !(n % i) ) { is_prime = 0; break; } } if ( is_prime ) { fact_time++; break; } while ( !(n % i) ) { n /= i; if ( fact_time < UCHAR_MAX ) fact_time++; } } if ( fact_time > 2 ) { printf("YES\n"); } else { printf("NO\n"); } return 0; }