you can copy and paste a column of 16 digit numbers into excel like this:

Open a new excel document.Leave it blank then click FILE / SAVE AS.From the type box, select "text (tab delimited file)" option.Format the column where you want to paste the 16 digit numbers as "text".Copy your 16 digit numbers from the original document (word, email, where ever they are) and paste them into the column in the tab delimited file that you just formatted as text. Save it again.You will see an error warning. Select all of your 16 digit numbers and select "ignore error" from the list of error handling options.Keep the file as a text file or save it as an excel file, it works either way. You might see the error warning again, just select all and ignore error again.