So, first we need to know that an integer is a whole number that can be - and + (Negative and positive). An integer cannot be a decimal nor a fraction.
So remember this and that's the way we can solve the following.
Number 1 is an integer.
Number 2 is an integer.
Number 3 is not an integer.
Number 4 is not an integer.
Number 5 is an integer.
I hope this helps! If it did, may i have Brainliest?