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For any positive integer \(\mathrm{n}\), the length of \(\mathrm{n}\) is defined as the number of prime factors whose product is \(\mathrm{n}\). For example, the length of \(75\) is \(3\), since \(75 = 3 \times 5 \times 5\). How many two-digit positive integers have length \(6\)?
When we say the length of a number is the count of prime factors, we're counting each prime factor every time it appears.
For example:
We need two-digit numbers (10-99) with exactly 6 prime factors.
List all partitions of 6 and associate with primes:
Only two numbers: \(64\) and \(96\).
Answer: 2.