How many iPhones did Apple sell last quarter?

The analysts' estimates range from 15 million to 20.25 million. Average: 16.9 million.

No product contributes more to Apple's (aapl) bottom line than the iPhone.

In the 2nd fiscal quarter that ended in March, when the company sold a record 18.65 million units, the iPhone and related products and services generated $12.3 billion in revenue, almost exactly 50% of Apple's total sales for the quarter -- more than the Mac, iPod and iPad combined.

So when Apple reports its 3rd quarter earnings next week, everybody who follows the company -- from its most steadfast investors to its fiercest competitors -- will be paying particular attention to how many iPhones it sold.

The estimates of the 39 analysts we polled for our quarterly earnings smackdown were all over the lot, from a high of 20.25 million from Traderhood's Nicolae Mihalache, a Romanian mathematician who teaches at the University of Paris and tends to overestimate, to 15 million from Needham's Charlie Wolf, a veteran Apple hand who tends to come in low.

The average all the estimates, 16.9 million, represents a 101% increase over the same quarter last year, and would bring the total number of iPhones sold over the past four years to more than 125 million.

The 39 analysts in our survey included 14 amateurs and 25 professionals. Their average estimates were closer than in past quarters. Among the amateurs it was 17.8 million. Among the pros, 16.4 million. We'll find out whose estimates were closest to the mark when Apple reports its earnings next Tuesday.

Below: The estimates we've gathered so far and the dates they were submitted. The Q2 rank numbers show how accurate each analyst's estimates were last quarter (the lower the better).

[UPDATE: Three more analysts have come in with iPhone numbers since this was posted: Wedbush's Scott Sutherland (18.65 million), UBS's Maynard Um (18.35) and CitiGroup's Richard Gardner (18 million). That brings the Wall Street consensus up to 16.6 million and puts the overall average above the 17 million mark.]

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Analyst, affiliationiPhones (millions)Date of est.Q2 rank
Nicolae Mihalache, Traderhood20.256/24/1116
Dennis Hildebrand, Apple's Gold18.906/24/1112
Chas McKenna, Apple Finance Board18.406/17/119
Mark Beauch, Apple Finance Board18.105/9/1113
Patrick Smellie, Apple Finance Board18.067/2/1110
Corey Forsberg, Apple Finance Board18.007/2/11NA
Robert Paul Leitao, Posts At Eventide18.006/25/116
Ralph Schackart, William Blair18.006/7/1144
Luke Kittell, Apple Finance Board17.806/24/118
Daniel Tello, Deagol's AAPL Model17.607/1/114
Mark Moskowitz, J.P. Morgan17.587/5/1123
Brian White, Ticonderoga17.537/12/1139
Navin Nagrani, Apple Finance Board17.506/26/11NA
Turley Muller, Financial Alchemist17.156/17/117
Matthew Hoffman, Cowen & Co.17.104/21/1122
Adam Thompson, Apple Finance Board17.037/3/1111
Andy Zaky, Bullish Cross17.006/22/112
Chris Whitmore, Deutsche Bank17.007/5/1137
Tavis McCourt, Morgan Keegan17.006/28/1120
Shaw Wu, Sterne Agee17.007/6/1129
Daniel Ernst, Hudson Square17.007/11/1146
Keith Bachman, BMO Capital16.707/11/11NA
T. Michael Walkley, Canaccord Genuity16.507/5/1135
Brian Marshall, Gleacher & Co.16.507/5/1126
Kathryn Huberty, Morgan Stanley16.506/26/1134
Jeff Fidacaro, Susquehanna16.446/7/1121
Ben Reitzes, Barclays Capital16.406/28/1141
Peter Misek, Jeffries16.307/7/1127
Scott Craig, Merrill Lynch16.156/7/1124
Bill Shope, Goldman Sachs16.057/6/1148
James Cordwell, Atlantic Equities16.007/6/11NA
Gene Munster, Piper Jaffray16.007/5/1140
Hendi Susanto, Gabelli & Co.15.967/8/1133
Robert Cihra, Caris15.807/11/1117
Toni Sacconaghi, Bernstein Research15.706/28/1115
Mike Abramsky, RBC Capital15.506/29/1118
Horace Dediu, Asymco15.106/26/115
Nehal Chokshi, Technology Insights15.107/7/1114
Charlie Wolf, Needham15.006/28/1136
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