Mihaela is the Romanian and Croatian feminine of Michael — from the Hebrew mi cha El, meaning "who is like God." The Archangel Michael is the namesake.
Mihaela is widely used in Romania. Simona Halep's full name is Simona Mihaela Halep.
Mihaela 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 Mihaela reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.