Anna is the Latin and Greek form of the Hebrew Hannah — from Channah (חַנָּה), meaning "grace" or "favour." In the New Testament Anna is a prophetess who recognises the infant Jesus in the temple.
Anna is one of the most widely used girl names in the world — found in some form (Anna, Ann, Anne, Anya, Annie) in nearly every European language. Today it sits in the U.S. top 60 and is consistently in the top 5 in many European countries.
Anna 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 Anna reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.