When working with large numbers in Google Sheets, you can convert them into millions (M) or thousands (K). Please see here if you work with Microsoft Excel.
Step 1: Select the axis from the chart you want to convert, e.g., y-axis;
Step 2: Select "Custom" in the "Number Format" box;
Step 3: Select "Other custom formats" from the drop-down list;
Step 4: Type #,##0.00,,"M" in the format box;
Step 5: The y-axis label will convert into millions;
Step 5: If you want to convert the y-axis into thousands, repeat the steps above and type #,##0,"K" in the format box. The y-axis label will convert into thousands (K).