PDFTK Builder - PDFTK Builder is a free graphical interface to for PDFTK, making it much easier to use.
PDFsam - PDFsam Basic, a free, open source, multi-platform software designed to split, merge, extract pages, mix and rotate PDF files
QPDF - QPDF is a command-line program that does structural, content-preserving transformations on PDF...
Adobe Acrobat DC - Make your job easier with Adobe Acrobat DC, the trusted PDF creator. Use Acrobat to convert, edit and sign PDF files at your desk or on the go.
iSafePDF - iSafePDF is a free open source PDF protection software.
PyPDF2 - PyPDF2 - A utility to read and write pdfs with Python