I would write, one thousand, three hundred and forty as:
1,340
Chat with our AI personalities
Three hundred thousand: 300,000 Forty three thousand: 43,000 Just in case you were asking for "three hundred forty three thousand": 343,000
you write it: six hundred million forty three thousand three three hundred twenty one.
four thousand and three hundred forty thousanths
eighteen thousand three hundred forty-five
three hundred forty thousand dollars