Ginger is from the Greek zingiberis — the rhizome spice — and used as an English nickname for red-haired people from the 19th century. Famously did everything Astaire did "backwards and in high heels" (the quote is from cartoonist Bob Thaves, 1982).
Ginger 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 Ginger reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.