Ābhūta-saṃplava & Loka-vibhāga
Dissolution Threshold and the Fourteen Abodes
तथा दशसहस्राणामयुतं कोटिरुच्यते / अर्बुदं दशकोट्यस्तु ह्यब्जं कोटिशतं विदुः
tathā daśasahasrāṇāmayutaṃ koṭirucyate / arbudaṃ daśakoṭyastu hyabjaṃ koṭiśataṃ viduḥ
Thus, a collection of ten-thousands is called ‘ayuta’, and it is also termed ‘koṭi’. Ten koṭis are called ‘arbuda’, and a hundred koṭis are known as ‘abja’.