#include <iostream> using namespace std; int main() { int n; int i; int dem=0; cout << "Nhap n: "; cin >> n; for(i=1;i<=n;i++) { if (n%i==0) dem=dem+1; } if (dem==2) cout << n <<" la so nguyen to"; else cout << n <<" khong la so nguyen to"; return 0; }