Number of universes under the many worlds hypothesis.

Every interaction that causes the collapse of a wave function tied to probability creates all possible outcomes in a new universe that forked from that moment.
That happens in every newly created universe, too.

The rate of creation of universes just by particle interactions in our universe is insane. But every one of those universes is spawning new universes just as fast, each of the spawned universes spawning new universes... yada yada.

There's no possible way to count these universes, but a google doesn't even cover what happened in the first nothingth of a second.