Plautilla is a Latin diminutive. Plautilla Nelli (1524-1588) was the first known Florentine female Renaissance painter — a Dominican nun at the Convent of Santa Caterina da Siena who taught herself painting by copying Fra Bartolomeo. The first woman to paint a Last Supper — her recently restored 7-meter masterpiece is now in Santa Maria Novella, Florence.
Plautilla 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 Plautilla reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.