Destiny is from the Latin destinata ("a thing destined, predetermined fate"). Destiny Cyrus — Miley Cyrus's birth name. Destiny Hope Cyrus is Miley's full birth name. The name is also closely associated with the 2014 Activision Blizzard video-game franchise Destiny and Destiny 2.
Destiny 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 Destiny reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.