The Tip of the Night for March 24, 2023, warned about Excel's tendency to cut off numbers with multiple decimal places. Excel will also round up whole numbers with many digits when files are imported into Excel. Here's some additional information on how you can import whole numbers into Excel from .csv files without having Excel round them up and
When importing .csv files into Excel from the Data tab on the ribbon using the From Text/CSV import tool, you will be prompted to detect the data type. By default Excel will base the format on the first 200 rows. In a field with a number with more than 11 digits, Excel will switch the format to scientific notation:
If you except the default settings, load the data, and then reformat the cells to display the whole number, you'll see all of the numbers have been rounded up and will end in zero.
You can avoid this problem when importing the .csv file by resetting the Data Type Detection to 'Do not detect data types'
. . . the file will import into an Excel worksheet with the numbers intact: