8-9 digits latitude/longitude format

Question

i have a database of latitude and longitude GPS coordinates in this format:

Latidude                        Longitude

20908403.7226004675030708 223749828.7524890005588531

20908403.7325199767947197 223749828.7432585060596466

20908403.2405762746930122 223749828.7983648478984833

I tried to do a 1/10^6 rescaling and the trajectory i obtained is the expected one, but i'm struggling too understand the format of the coordinates and their physical meaning.

In my opinion those cannot be:

• decimal degrees: 52.145339, 5.331997;
• NE coordinates: 52°08'43.2"N 5°19'55.2"E;
• Some kind of ECEF-like coordinates;

and i'm out of options.

Thank you in advance for your help, greetings.

Alessandro

Update:

The format was a "proprietary" one by the company we were working for.

Answer 1

Probably, this format is to "increase" the accuracy with more decimal digits. But, it is important to know the following: be careful with the number of digits