This is simply default Excel behaviour. Numbers that are very long (such as 447787574382) are represented in exponential notation.
The solution is therefore to do the conversion. After that, open the resulting Excel file and select ALL the numbers from the number column, then right click on them and choose "Format Cells" option. Then instead of the "General" choose the "Number" and set number of decimal places to 0.
This article refers to Able2Extract and Able2Extract Professional.