The original Temple Run was a runaway hit with more than 170 million downloads over its lifetime, and the game’s sequel, which was released last week, is shaping up to be just as successful.

Imangi Studios just announced that the newest iteration of Temple Run, Temple Run 2, has been downloaded a record 20 million times after just four days on the App Store. It hit the number one spot on the Top Free Apps chart in the App Store within eight hours of its release and it has remained there ever since.

The developer threw in a few other stats, letting us know that in under a week, users played 210 million sessions of Temple Run 2, for a combined time of more than 1,775 years of gameplay. That makes for one impressive release.

If you’re not familiar with Temple Run 2, it is an endless runner that incorporates gesture based gameplay for an overall experience that is addictive, thrilling, and a ridiculous amount of fun.

While it is based on the successful original game, Temple Run 2 features new game mechanics such as a mine cart and a zip line, new power ups, and most importantly, updated graphics and more fluid gameplay.

The best part about Temple Run 2 is that the developers have truly mastered the freemium model. You don’t need to pay to play, but if you want to ramp up your score and keep going after making a mistake, you might need to shell out a bit of cash. Paying cash is entirely optional, which is what’s rocketed Temple Run 2 to App Store fame.

Temple Run 2 is available for the iPhone, iPad, and iPod touch as a free download from the App Store.