Permutation and CombinationHard
Question
The number of proper divisors of apbqcrds where a, b, c, d are primes & p, q, r, s ∈ N is -
Options
A.pqrs
B.(p + 1) (q + 1) (r + 1) (s + 1) - 4
C.pqrs - 2
D.(p + 1) (q + 1) (r + 1) (s + 1) - 2
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