2 tables, each table 18 people;
3 tables, each table 12 people;
4 tables, 9 people per table;
6 tables, 6 people per table;
9 tables, 4 people per table;
12 table, 3 people per table;
18 table, each table has 2 people;
One small table per person (36 tables, each 1 person)