Yumna (يمنى) is the Arabic word for "right side" — by extension, "good fortune" or "blessed" (the right side being the side of blessing in Arab tradition). From the same root as Yemen.
Yumna is widely used across the Arab world.
Yumna 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 Yumna reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.