Hekuba (Ἑκάβη) was the great Queen of Troy — wife of King Priam and mother of nineteen children including Hector, Paris, Cassandra, and Polyxena.
Hekuba 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 Hekuba reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.