Il numero 644, seicentoquarantaquattro in Italiano, in Inglese si dice six hundred forty-four.
Il numero ordinale 644° in inglese si dice six hundred forty-fourth.
635: six hundred thirty-five
636: six hundred thirty-six
637: six hundred thirty-seven
638: six hundred thirty-eight
639: six hundred thirty-nine
640: six hundred forty
641: six hundred forty-one
642: six hundred forty-two
643: six hundred forty-three
645: six hundred forty-five
646: six hundred forty-six
647: six hundred forty-seven
648: six hundred forty-eight
649: six hundred forty-nine
650: six hundred fifty
651: six hundred fifty-one
652: six hundred fifty-two
653: six hundred fifty-three