Lightroom Classic CC has stitching capabilities. However, 600 images is rather significant and I question if it would have the capability to handle an image that large. There is no stitching capability in Lightroom CC.
I'm providing you with a link to a product called Gigapan. I know, it is a hardware device for mounting a camera for taking still images to create high-resolution panorama images. But they seem to have software for stitching large numbers of images together, and I don't know if the software can be purchased separately. It might be something for you to consider. For the number of images you are wanting to work with, I have the feeling you will require something more than what Lightroom will handle. I believe Lightroom has a 65,000 pixel limit for one side of an image. From your description it would seem that you are looking to exceed such a limit.
GigaPan | High-Resolution Images | Panoramic Photography | GigaPixel Images