Gina is the Italian diminutive of names ending in -gina (such as Regina, queen, or Giorgina) — also independently used in Hebrew (גינה, gardener). Campbell (1968, David di Donatello Best Actress). Gina Torres (Suits). Gina Carano (The Mandalorian).
Gina 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 Gina reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.