Excel IF-formula with multiple conditions from 4 columns

Got values (people's age) in columns B, C, D and E. I'm trying to get output "2" if age is below 23 or above 67. But I have to take into account that there may be celles present with text and maybe cells holding value 0, or even blank. So I got this formula for column B:

=IF(ISNUMBER(B2),IF(OR(AND(B2>0,B2<23),B2>67),2,""),"")

Formula works, but I want to do the same thing with columns C, D and E - and put it all into one formula. This should have output "2" if any of the 4 columns meet my age-conditions. And my problem is that I clearly don't have the skills to pull this off... Anyone that can help me out?