For a processor with model number atom e665c and a TDP of 3.6 W, what is the sSpec number?
create table table_16729930_18 (sspec_number varchar, tdp varchar, model_number varchar, PRIMARY KEY (sspec_number))
select sspec_number from table_16729930_18 where tdp = "3.6 w" and model_number = "atom e665c"