When Meena turned 16 years old, her parents gave her a cake with $n$ candles, where $n$ has exactly 16 different positive integer divisors.  What is the smallest possible value of $n$?
To find the smallest possible value of \( n \) that has exactly 16 different positive integer divisors, we need to consider the number of divisors function. For a number \( n \) with prime factorization \( n = p_1^{e_1} p_2^{e_2} \cdots p_k^{e_k} \), the number of divisors \( d(n) \) is given by:

\[
d(n) = (e_1 + 1)(e_2 + 1) \cdots (e_k + 1)
\]

We need \( d(n) = 16 \). The possible factorizations of 16 are:

1. \( 16 = 16 \times 1 \)
2. \( 16 = 8 \times 2 \)
3. \( 16 = 4 \times 4 \)
4. \( 16 = 4 \times 2 \times 2 \)
5. \( 16 = 2 \times 2 \times 2 \times 2 \)

We will consider each case to find the smallest \( n \).

**Case 1:** \( n = p_1^{15} \)
- The smallest prime is 2.
- \( n = 2^{15} = 32768 \)

**Case 2:** \( n = p_1^7 \cdot p_2 \)
- The smallest primes are 2 and 3.
- \( n = 2^7 \cdot 3 = 128 \cdot 3 = 384 \)

**Case 3:** \( n = p_1^3 \cdot p_2^3 \)
- The smallest primes are 2 and 3.
- \( n = 2^3 \cdot 3^3 = 8 \cdot 27 = 216 \)

**Case 4:** \( n = p_1^3 \cdot p_2 \cdot p_3 \)
- The smallest primes are 2, 3, and 5.
- \( n = 2^3 \cdot 3 \cdot 5 = 8 \cdot 3 \cdot 5 = 120 \)

**Case 5:** \( n = p_1 \cdot p_2 \cdot p_3 \cdot p_4 \)
- The smallest primes are 2, 3, 5, and 7.
- \( n = 2 \cdot 3 \cdot 5 \cdot 7 = 210 \)

Among these cases, the smallest value of \( n \) is found in Case 4:

\[
n = 2^3 \cdot 3 \cdot 5 = 120
\]

Thus, the smallest possible value of \( n \) that has exactly 16 different positive integer divisors is \( \boxed{120} \).