Apple CEO Steve Jobs will have something more to boast about when he hits the stage in September at a rumored iPod announcement: iPhone sales numbers.

The Cupertino, California, Mac maker is on track to sell 4 million iPhones when Apple’s chief addresses the San Francisco crowd, according to RBC Capital Markets analyst Mike Abramsky.

“We continue to expect iPhone upside (our outlook remains 14M CY08, 24M CY09), along with ‘halo effect’ impact to global Mac sales,” he wrote in a note to clients.

He attributes the iPhone momentum to its recent international expansion—Apple on August 22 launched iPhones into 21 new countries—and its Best Buy distribution deal announced September 7.

At Apple’s upcoming September 9 event, the company is expected to update its iPod line, including redesigned iPod Nanos, and cut prices, among other announcements.

RBC's analyst said Apple may also be mulling a lower-cost “iPod Phone,” a voice-only one priced below $99 with a service contract. That phone would target international sales and push Mac sales worldwide, the analyst noted. He said it wasn’t expected at the upcoming event.

RBC makes a market in Apple shares.