Okay, somewhat difficult to say...I believe it is a type of
Mammillaria. It looks to be dichotomous (branching-splitting into 2 heads).
Mammillaria perbella & ,
parkinsonii are known to do this (although they are not the only ones). They are both variable. I think
M. perbella has darker pink blooms, so I'm leaning toward
M. parkinsonii. This is a very large genus, so that's my best educated guess.
