Twelve thousand [and] thirty.
Twelve and thirty-two hundredths.
Thirty-seven and twelve thousandths.
Twelve and thirty-two hundredths
twelve and thirty-four hundredths.
Twelve and thirty-five thousandths.
Twelve thirty in the afternoon would be most correct. You cannot say twelve thirty o'clock. You only say o clock when you don't have any minutes over.
Two thousand and twelve
Twelve and thirty-nine thousandths.