Banks is from the Old English banke (riverbank, slope) — a surname-to-given-name in modern American naming. Jeffrey Banks — American fashion designer. Banks Repeta — American child actor. Banks also recalls Mary Poppins (Mr. Banks the patriarch).
Banks 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 Banks reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.