Cc1c(Cl)ccc2c1NC(=O)C21NC(CCC(N)=O)[C@H]2C(=O)N(c3ccc(Cl)cc3)C(=O)[C@H]21
Heavy atom refers to any atom that is not hydrogen. The heavy atoms in molecules are carbon, oxygen, nitrogen, and sulfur. How many heavy atoms are in the molecule?