Whoopi is the stage name chosen at age 18 by Caryn Elaine Johnson (born 1955) — partly from a whoopee cushion ("I made noises like one") and partly from the Yiddish-influenced exclamation "whoopi" that was Black show-business slang.
Whoopi 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 Whoopi reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.