Prime Factorization of 21609 Factoring Prime Factors of 21609 Use the form below to do your conversion, separate numbers by comma. prime factorization calculator of 21609 Prime Factors of 21609 =3, 3, 7, 7, 7, 7 Which is the same as = 32 x 74 Prime Factors Tree of 21609 21609 / \3 7203