Bhūtasaṅkhyā system is a method of recording numbers using ordinary words having connotations of numerical values. The method was popular among Indian astronomers and mathematicians since ancient times.
The number "four" can be associated with the word "Veda (वेद)" as there are four Vedas. In a similar manner, various numbers are associated with suitable words. A non-exhaustive list used by the current system can be found here.Learn more