Trillions rhymes with:
billions, brazilians, civilians, hillians, jillions, millions, pavilions, reptilians, zillions, australians, battalions, billions, brazilians, civilians, hillians, italians, jillions, medallions, millions, pavilions, rebellion's, rebellions, reptilians, scallions, somalians, stallions, zillions
Trillions sounds like:
thrilling, trailing, trilling, trolling, twirling