Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
Microsoft 365 - Boost your productivity with reliable access anywhere with services like email, calendar, file sharing, meetings, instant messaging, and Office Online
Okular - Okular is a universal document viewer based developed by KDE.
Apache OpenOffice - Apache OpenOffice is an open source, office document productivity suite.
PDFill - Open, View, Edit, Save and Print PDF Documents without Adobe Acrobat
SSuite Office - SSuite Office is called to be one of the most accomplished software developers for both beginners and professionals alike.