I had a project for Android Studio, with a name "example001" both the folder where the project is, and internally the internal code that name, as I can change its name for example "Program X"
I follow these steps, but not all names are changed internally.
Greetings.
To rename the name of the package, you can do it as indicated
right button in package > Refactor > Rename , in some cases the following window will appear:
indicates the confirmation to refactor the package in those incidents.
To finish check in your files build.gradle of the application, the property applicationId that you have to change manually.
This method only works for the last segment of the package.