Follow the steps noted below when creating a primitive prism.
Using the Function:
Select Prism from the Create>Primitive Solid submenu. The Create Prism dialog appears.
Configure the prism through the Create Prism dialog, and select OK when done.
Select the base center position through the Universal Position Menu.
The prism is created per your specifications, and positions it at the base center you indicated.
Above > Prism created using the default settings (View 7)