number to words

[invigorzz313]

Number to words

Close #3890

Checklist:

• [x] I have mentioned the issue number in my Pull Request.
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have created a helpful and easy to understand README.md

[invigorzz313]

@MohitGupta121 @TusharKesarwani Kindly review this PR.