COC(=O)C1Cc2c([nH]c3ccccc23)-c2[nH]c3ccccc3c2CC(NC(C)=O)C(=O)N2CCCC2C(=O)N1
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?