This is production and you don't want to start SUM on this system.
You want to know what version of SUM it is.
You can check the manifest.mf file for the SUM version without needing to start SUM:
> cd <SUM PATH>\SUM
> more summanifest.mf
keylocation: SAP AG
compilation mode: UNICODE
compiled for: 64 BIT
support package: 7
patch number: 2
native branch: lmt_008
java branch: lmtj_008_REL
assembly time: 2013-05-13 05:10:16
pack version: 22
pack tool version: 1.042
You are interested in the lines:
"release", "support package" and "patch number".
The example above is therefore SUM 1.0 SP07 patch 2.