√4 is a _____ number.

As we know, the numbers expressed in p/q form are known as rational numbers.

Here, p and q are integers, and q ≠ 0.

We know that,

 √4= 2

So this is a rational number. We can express this number in p/q form.

For example: $2=\frac{2}{1}$

Irrational numbers can't be expressed in p/q form. Therefore, 2 is not an irrational number.