Since u already have a file, its better to use a command line utility like sygwin etc to do this work for you. no sense trying to import it into sql table only to export it back as an excel sheet.

I would probably use cygwin to split the files into the number of columns required and then simply change the format to csv in order to opn it in excel.

You cud try another database like filemaker

http://help.filemaker.com/app/answers/detail/a_id/7541/~/technical-specifications-of-filemaker-pro-11-and-filemaker-pro-11-advanced

which support upto 256 mil columns per file.

Its also pretty easy to import data and export data from it , but the upload takes a long time to complete