Hindustani numerals

As with many Indo-Aryan languages, Hindustani (Hindi-Urdu) has a decimal numeral system that is contracted to the extent that nearly every number 1–99 is irregular, and needs to be memorized as a separate numeral.

Numbers from 100 up are more regular. There are numerals for 100, sau; 1,000, hazār; and successive multiples by 100 of 1000: lākh 1,00,000 (10⁵), kroṛ 1,00,00,000 (10⁷), arab 1,00,00,00,000 (10⁹, billion), kharab 1,00,00,00,00,000 (10¹¹), nīl 1,00,00,00,00,00,000 (10¹³), padma 1,00,00,00,00,00,00,000 (10¹⁵, quadrillion). (See Indian numbering system.) Lakh and crore are common enough to have entered Indian English.