Let $p_1, p_2, p_3, p_4$ be four distinct prime numbers, and let $1 = d_1 < d_2 < \ldots < d_{16} = n$ be the divisors of $n = p_1 p_2 p_3 p_4$. Determine all $n < 2001$ such that $d_9 - d_8 = 22$.

Let's think step by step and output the final answer within \boxed{}.
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