COc1ccc(C2c3[nH]c4ccccc4c3C[C@H]3C(=O)N(C4CCN(Cc5ccccc5)CC4)CC(=O)N23)c(OC)c1
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?