Export values are not consistent across different exported file type (Excel, csv, xml, html)

Issue Summary

When exporting Number Custom Field values that are long, it would lead to some inconsistencies based on the file type exported. Below is the observed results:
In this example, the value is 100,000,000,000,000

Steps to Reproduce

1. Create a Number Custom Field
2. Add the field into a Screen
3. Add long numeric value into the field (e.g.: 100,000,000,000,000)
4. Search for this issue from Issue navigator and Export

Expected Results

All exported file types should have the same value shown in UI

Actual Results

The exported file types have inconsistent formats