String in String (number)

I want to check if there are numbers 2x (or 3x) in a variable, for example for
$var = 47253
it should return false or 0. For
$var = 47252     or     $var = 47242
it should return true or 1. And for
$var = 47222
it should return false or 0

If that's not possible, I want to check for the number of strings in a function, for example if i have
$var = 58355
I want to check for 5 in this variable, and it should return 3. For
$var = 73642
Check for 7 it should return 1