http://www.androidpolice.com/2017/06/13/google-sold-one-million-pixel-devices-according-pixel-launcher-download-figures-play-store/
Google has only sold about one million Pixel devices, according to Pixel Launcher download figures from the Play Store
Of all the smartphones and tablets that Google has released in recent years, those from the Pixel line have likely sold the most. I've personally seen more "regular people" using Pixel phones than any Nexus devices, and that can be attributed in large part to Verizon officially carrying the Pixel and Pixel XL. However, since Google never releases sales figures for its mobile devices, it's been difficult to tell precisely how many Pixels have been sold - until now.
Our old friend Ron over at Ars Technica first noted this after noticing that the Pixel Launcher had just crossed the one million download threshold. Now, we couldn't make this connection with, say, the Google Now Launcher and Nexus devices since the GNL was only exclusive to the Nexus 5 for a little while, but the main version of the Pixel Launcher can still only be downloaded on two devices via the Play Store: the Pixel and the Pixel XL (the Pixel C gets its own, separate APK). Yes, there are nearly 1.4 million Pixel Launcher downloads on APK Mirror, but those obviously don't count towards Play Store numbers, and we highly doubt that Pixel users are going to APKM to download something they can easily get from the Play Store.