Not on screen but, I have a D7000 and serial number for that camera is in the EXIF data of each image it takes. GIMP can view/edit metadata. For my D7000 camera...
Open JPG/RAW image in GIMP
Menu --> Image/Metadata/View Metadata
Select "Exif" tab at top
Look in "Exif Tag" column
Scroll down and look for "Exif.Nikon3.SerialNumber"
The number in the "Value" ...