Since Vedic times Hindus were able to describe very large numbers by using appropriate names. The 9 numbers were already mentioned in RV like eka, dwi, tri, chatur,......., nava.
The names for 10, 20,..., 90 occurs in RV 2.18.5-6. Other numbers are described thus- for example 84 is spelled as four plus eighty. 18 is spelled as 2 less than 20 and so on.
RV 3.9.9 for example has the number 3339 spelled as three thousand, three hundred, and 39.
The YV 17.2 mentions numbers upto ten raised to the power of 12.
इमा मेऽअग्नऽइष्टका धेनवः सन्त्वेका च दश च दशु च शतं च शतं च सुहस्रं च
सहस्रं चायुतं चायुतं च नियुतं च नियुतं च प्रयुतं चार्बुदं च न्यर्बुदं
च समुद्रश्च मध्यं चान्तश्च परार्द्धश्चैता मेऽअग्नऽइष्टका धेनवः
सन्त्वमुत्रामुष्मिँल्लोके॥॥
...............
Bhavarth. O learned person, may the materials of my yajna, like
milchkine, be the givers of happiness to me. They may be one, and ten,
and tentens, a hundred, and ten hundred, a thousand and ten thousand
and a hundred thousand, a lac and ten lacs, a million, and ten
millions, a crore, ten crores, hundred crores, thousand crores, its
tentimes Maha Padma, its ten times Shankh, its tentimes Samudra, its
tentimes Madhya, its tentimes Prardh.. May these bricks of my altar be
a source of happiness to me, like milch-kine in this world and the
next World.
For example: ayuta is 10^4 (10 raised to the power of 4), niyuta is 10^5, payuta is 10^6, arbuda is 10^7, nyarbuda is 10^8, samudra is 10^9, madhya is 10^10, anta is 10^11, pararardha is 10^12 etc.
Similar list can be found in Taittiriya Samhita 4.4.11, MaitrAyani Samhita 2.8.12, Kathaka Samhita 17.10 etc.
The AV 8.3.21 for example mentions the following number:
shatam te ayutam hyanan dwai trini chatvAri krama
Here shatam= 100, ayutam=10,000, dwai=2, trini=3, chatvari=4. The number is to be read in a reverse order by the standard convention.
Shatam te ayutam is one million. So, the number is 432 million.
Also, the Chamaka mantras found in the Yajur Veda also describe certain numbers as follows:
navadasha cha me ekavimsatih cha me
( 9 and 11)
trayodasha cha me panchadasha cha me saptadasha cha me
( 13, 15 and 17)
ekatrimshat cha me trayatrimshat cha me
(31 and 33)
........
dvatrimshat cha me shattrimshat cha me
(32 and 36)
chatvarimshat cha me chatuschatvarimshat cha me
( 40 and 44)
etc... (Mantras from YajurvEda)
Abbreviations used
RV 2.18.5 ---> Rig Veda Samhita Mandala 2, Sukta 18, Mantra 5.
YV 17.2 ----> Adyayaya 17, Mantra 2 of Yajur Veda Samhita.
AV 2.6.1 ---> Atharva Veda Samhita, Kanda 2, Sukta 6, Mantra 1.