Savitri (सावित्री) is from the Vedic deity Savitr (the impeller, the sun). The archetype of devotional wifely strength in Indian tradition — Vat Savitri Vrata is named for her.
Savitri 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 Savitri reduce to 8, The Visionary. This is a traditional interpretive system, not a factual claim about the name.