O=c1c(Cc2c(O)ccc3ccccc23)nnc2sc(-c3nn4c(=O)c(Cc5c(O)ccc6ccccc56)nnc4s3)nn12
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?