Hindu methods for finding factors or divisors of a number

Abstract

Factoring or finding divisors of a number does not appear as a subject of treatment in any early work on Hindu arithmetic. There are, however, reasons to believe that the ordinary method of factoring a number by successive division by 2, 3, 5, etc. was well known but being much too elementary was not considered suitable for inclusion in an arithmetical work. Even in Mahāvīrācārya’s (850 ad) voluminous Gaṇitasārasaṅgraha where we have explicit references to factorisation no rule has been stated for the purpose. Śrīpati (1039 ad) is probably the first Hindu writer who has formally dealt with the subject of factoring a number in his Siddhāntaśekhara. Besides stating the ordinary method based on successive division, he gives an additional method for factoring a non-square number by expressing it as a difference of two squares.