Is it ok to be friends with an ex?

I dated this guy my sophomore year of high school... I feel like he’s more of my childhood friend than my ex.

When stopped talking for awhile but we still talk every once in awhile

I have no feelings for him now

I am a sophomore in college so me dating him was 4 years ago

I have a new boyfriend, I’ve been dating him for 2 years and I love him

And my ex is friends with some of my friends so we were all texting and wanting to hang out. Is it ok if I become friends again with my ex??