Use MS Access. I have a file of 2,673,404 records. It will not open in notepad++ and excel will not load more than 1,048,576 records. It is tab delimited since I exported the data from a mysql database and I need it in csv format. So I imported it into Access. Change the file extension to .txt so MS Access will take you through the import wizard.
MS Access will link to your file so for the database to stay intact keep the csv file