How many people live in an area that has a population in Rosenthal smaller than 2,460 while having a population of 4,639 for Glegallan as well as having an Allora population greater than 2,106?
CREATE TABLE "population" (
  "year" real,
  "population_region_total" real,
  "population_stanthorpe" real,
  "population_warwick" real,
  "population_allora" real,
  "population_glengallan" real,
  "population_rosenthal" real
);
SELECT COUNT("population_region_total") FROM "population" WHERE "population_rosenthal"<'2,460' AND "population_glengallan"='4,639' AND "population_allora">'2,106';