B737 pilot reported during taxi for takeoff at night encountering another aircraft stopped on the taxiway; resulting in the air crew taking evasive action to avoid a collision with the other aircraft.

Narrative

Nighttime redeye departure from ZZZ. Pushed back from X gates and was given taxi instructions to taxi to RWY XXR via taxiways 1 and 2. It was now dark at night. Taxiing at a normal speed southbound on 1; and had to come to an abrupt stop due to Aircraft Y stopped on 1 approximately abeam Gate XX. Ground had not given any heads-up about the stopped aircraft. Unsure if it had pushed back there from gates or just told to hold short there. It was extremely difficult to visually see this aircraft due to a couple reasons. First; the white LED wingtip navigation lights that shine in back of this aircraft are very bright and tend to wash out the normal view of the rest of the aircraft fuselage until you're very close to it. Secondly; when on this ZZZ taxiway 1 pointed south abeam the gates; the cultural city lighting of the surrounding local area including lighting on surrounding hills tends to make even the bright LED wingtip navigation lights almost impossible to discern apart from the cultural lighting until very close. The FO and I even remarked how when Aircraft Y started taxiing again; that it virtually disappeared very quickly back into the cultural lighting; even though it was not far away.