Silvia is from the Latin silva (forest, wood) — also the modern Italian, Spanish, Portuguese, and German form of Sylvia.
Subject of countless Swedish royal histories.
Silvia 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 Silvia reduce to 9, The Giver. This is a traditional interpretive system, not a factual claim about the name.