Roberta is the feminine of Robert — from the Old Germanic hrod ("fame") + beraht ("bright") — "bright fame." A top-100 US baby name from 1924 to 1947, peaking at #44 in 1936. 1.
Roberta 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 Roberta reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.