Never "thirty hundreds." "Thirty hundreds" would be 30 × 100 = 3,000. The correct term is "thirty thousand."
Whether you are writing a bank check, drafting a legal contract, or teaching elementary math, expressing numbers in text form ensures absolute clarity. This comprehensive guide covers how to write, pronounce, and use the number 30,000 in various contexts. How to Write and Spell 30,000 in Words 30000 in words