Reversing True to False

[daffodil11]

Is there a function or value I can apply to another function to reverse the True/False value?

ISNUMBER(SEARCH(1,1)) = TRUE, but I want to know =ISNOTANUMBER(SEARCH(1,1)) = TRUE.

I'm looking for ways narrow a range a range such as using SUMIF(range1=a1,if(range2=/=number,etc))

I've tried ISTEXT, ISNONTEXT, ISNUMBER, ISERR, ISNA, but am having trouble coming up with the correct statement.

[JieJenn]

Maybe

NOT(ISNUMBER(SEARCH(1,1))) ?

[daffodil11]

NOT.

Today, I was a fool.