The fourth root of $16$ is $2$.

To determine the fourth root of $16$, we need to find a number that, when multiplied by itself four times, equals $16$. This is mathematically expressed as $\sqrt[4]{16}$.

Let’s start by examining the prime factorization of $16$. The number can be expressed in terms of its prime factors as follows:

Since we are seeking the fourth root, we need to identify a number that, when raised to the power of $4$, equals $16$.

In this case, we find that

Therefore, the fourth root of $16$ is indeed $2$, as demonstrated by the multiplication:

Another way to understand this concept is through exponents. The fourth root of a number can also be represented as raising that number to the power of $\frac{1}{4}$. Therefore, we can express $\sqrt[4]{16}$ as

Utilizing a calculator or recognizing that

we can simplify this expression:

Thus, we confirm that the fourth root of $16$ is $2$.