That's what I thought too, so I tried re-downloading it. Tried on mobile network (LTE) and Wifi from the device itself using multiple browsers. In my file browser it shows up with a logo on the APK, but on installation it doesn't even start.
Running Android 7.0 on Nexus 6,
Kernel: 3.10.40-g57ab30e
android-build@wpiw15.hot.corp.google.com #1
Thu Dec 8 04:23:22 UTC 2016