Each equation contain a different arbitrary constant: 1500, 2800, and 5 E20.
It can be assumed that each arbitrary constant has exactly the right units to make everything come out right...
It is sloppy to not specify the units of these constants...
Edited for example:
I could conduct experiments on the dynamics of falling objects, and publish that the distance of fall from rest, in metres (D), and the time of fall, in seconds, (t) seem to be related, and the best fit gives:$$D \approx4.9 \times t^2$$without implying that the units of distance are time squared...