How to display millions as M

Right click the cell containing the number, choose format cells

Choose Customer as Category, type in #,##0.0,,"M" in the Type: box, click ok

The number of zeros behind the decimal point will decide how much decimal places to show. For example a cell with 1190000 typed in will show 1.2M for #,##0.0,,"M" as custom format.

If you need a dollar sign in front, just use  $#,##0.0,,"M"