The safest way (does not depend on which spreadsheet you are using) is to go to the top of the column you want to invert, in the next cell (if your column is A1:A5500 or however many rows are in the column, you would start in cell B1... beside the row you want inverted)
You enter a 1. Use the auto fill handle to drag that cell in B1 down to the end of your column... this should leave the column with 1 in row 1, 2 in row 2, etc...highlight the column you just made. If you are in cell B1, control+shift+down arrow will select the entire column containing data. Once selected, look for the sort feature, and click sort Z to A, when it asks, click "extend selection" so the column you want is also sorted. BOOM, the column is inverted! You can then safely delete the temporary "helper row" you created.
There are fancier and more complex ways to do this, but I use this method all the time when importing draw history to get the dates going from oldest to newest, and making sure the correct draws sort with the dates.
Always make a copy of your original sheet in case something goes wrong, also control+z un does the last move.
Feel free to ask for more detail if you need it.
