Madalena is the Portuguese form of Magdalene — referring to Mary Magdalene, the disciple of Jesus from Magdala. Saint Mary Magdalene is the patron saint of Portugal's Madalena communities.
Madalena is widely used in Portugal and Brazil.
Madalena 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 Madalena reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.