Autodesk taking up 644 GB on a 349 GB Drive?

So, I was getting rid of items I didn't need and noticed this. Does anyone know why this happens? Is it just me, or does anyone else get this?

 

 

It means MB; I have that installed, and it's 644 MB.

Damn. I was hoping I'd stumbled upon the holy grail of hard drives.

Not sure what kicked this up, but its no longer relevant; locking.