"iPhone 5 pre-orders have shattered the previous record held by iPhone 4S and the customer response to iPhone 5 has been phenomenal," said Philip Schiller, Apple's senior vice president of worldwide marketing.
Apple unveiled the new version of its iconic smartphone last Wednesday and opened up pre-orders on Friday.
The first customers in the United States and several other countries are expected to get the device September 21, but Apple said some would have to wait.
"Demand for iPhone 5 exceeds the initial supply and while the majority of pre-orders will be delivered to customers on September 21, many are scheduled to be delivered in October," an Apple statement said.
The iPhone 5 will be available from the Apple Online Store and its retail stores, and for US customers through AT&T, Sprint, Verizon Wireless, Best Buy, RadioShack, Target and Walmart stores and other resellers.