Nika (Ника) is the Russian short form of Veronika — from the Greek nikē (victory). The Greek goddess Nike was the personification of victory. Used as a standalone Russian feminine name.
Nika is widely used in Russia.
Nika does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Nika reduce to 8, The Visionary. This is a traditional interpretive system, not a factual claim about the name.