If we would like to calculate roughly how many collisions there

have been so far in the life of a particle since the
beginning of the world, we could start from the fact
that the collisions for a gas molecule at normal
temperature and pressure are in the range of 10¹⁰
per second.

In the liquid state they are in the same order of magnitude.

There are many more inside a star.

There are over 2 × 10¹⁷ collisions per second.

In the initial fireball of the Big Bang
there must have been even more.

In interstellar space, where the particle was at some time, there are far fewer.

If we accept an average of 2 × 10¹⁵
we would not be far wrong.

With so many collisions per second,

for the 5 × 10¹⁷ seconds of the history of the World
we can say that

each particle must have suffered from the beginning
of the world till today some 10³³ collisions.