To determine if there exists a number $n$ that can be expressed as the sum of 2017 perfect squares in at least 2017 distinct ways, we consider the properties and combinations of perfect squares.

### Step 1: Understanding the Problem
The problem asks us to express a number $n$ as the sum of 2017 perfect squares, $n = a_1^2 + a_2^2 + \cdots + a_{2017}^2$, where $a_i$ are integers. Moreover, this can be done in at least 2017 different ways, meaning there are at least 2017 distinct sets of such integers.

### Step 2: Exploring Perfect Squares
Perfect squares are non-negative numbers of the form $k^2$, where $k$ is an integer. To construct different sums, we need to evaluate how the combinations of these squares can vary and still yield distinct sums that equate to the same $n$.

### Step 3: Existence of Solutions
1. Many Small Squares: By choosing different arrangements of small perfect squares (like 0, 1, 4, 9, etc.), we can vary them freely since they don’t drastically alter the cumulative sum quickly. For instance, using 0 is trivial as it adds nothing to sums; including or excluding it in varying positions introduces variety.

2. Adjusting a Larger Value: Consider including a larger square, say $(k+1)^2$, and adjusting the rest of the terms accordingly. This diversity of combinations even with fixed values of $a_i = 0$ (i.e., not all contributing to sum) provides additional distinct setups.

### Step 4: Conclusion
Given the vast number of combinations possible with 2017 variables, it is feasible to achieve at least 2017 distinct sums since:

- Choosing different subsets of minimal contributions (e.g., many zeros and small numbers) can still lead to varying sums.
- Incremental adjustments in a few selections using larger squares or varied middle-range integers allow differential assembly leading to the target sum.

Thus, there is indeed a number $n$ that can be expressed as the sum of 2017 perfect squares in at least 2017 distinct ways.

Hence, the answer is:
$$\boxed{\text{Yes}}$$