Mariana is a Latin compound name combining Maria (Hebrew Miriam — "beloved/longed-for child") and Anna (Hebrew Hannah — "grace"). The name was given to honor both Mary the mother of Jesus and Saint Anne, her mother.
Mariana is among the most popular girl's names in Brazil, Portugal, Spain, and Latin America. In the U.S. it sits in the top 200 and is rising. Four syllables, two saints, double the grace.
Mariana 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 Mariana reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.