Has a FIBA World Cup game ever ended 109-66?
Exactly once. On June 29, 2018, Nigeria beat Uganda 109-66, and no FIBA World Cup game before or since has ended that way. When it happened it was a scorigami, the first 109-66 in league history.
That makes 109-66 the 475th most common final score out of 1,178 that have ever occurred in FIBA World Cup. One point away, 110-66 has happened 1 times and 109-67 has happened never.