Lucrezia is the Italian form of Lucretia — from the Roman family name Lucretius, meaning "rich" or "profit." Lucrezia Borgia (1480-1519), the Renaissance Italian noblewoman, is the most famous bearer.
Lucrezia is widely used in modern Italy.
Lucrezia 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 Lucrezia reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.