select version () gives me output something like this
PostgreSQL 9.5.4 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.1.2 20080704 (Red hat 4.1.2-55), 64 bit.
Is there any other way to find
If memory serves the commercial version put out by EnterpriseDB uses a 4-part versioning scheme so the above would seem to be the community version you are looking at.
Otherwise maybe someone with access will be kind enough to provide the version their 9.5 version of the EnterpriseDB install outputs for comparison.
You can always check the O/S package manager and try and figure out how it was installed.
