How do you say factory in English?

Subsidiaries (collectively referred to as subsidiaries and factories);

If you translate XX factory directly, you'd better say: XX company/plant/factory/branch;

Divison is also a very professional usage, which is often used by multinational companies to represent a certain business (large) department, such as automobile department and electronics department. Automobile Divison is not necessarily an automobile branch, but should be called "Automobile Department".