Akiko (秋子 or 明子) combines aki (autumn, or bright) and ko (child) — "autumn child" or "bright child."
Princess Akiko of Mikasa (born 1981) is the great-granddaughter of Emperor Taishō. Akiko Yosano (1878-1942) was the iconic Japanese poet and feminist.
Akiko 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 Akiko reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.