Join our CAD community forums where over 25,000 users interact to solve day to day problems and share ideas. We encourage you to visit, invite you to participate and look forward to your input and opinions. Acrobat 3D, AutoCAD, Catia, Inventor, IronCAD, Creo, Pro/ENGINEER, Solid Edge, SolidWorks, and others.
What you need to do is open your part/assembly and go to Tools-Options-Document Properties-Units. There you will be able to change how many decimal places you want in you mass properties. Hope this of help to you.