188424domain: NAppears in sequencesSmallest number m such that sigma(m) has exactly n distinct prime factors.at n=6A152562Smallest number m such that sigma(m) = A002110(n) where A002110(n) is the product of the first n primes.at n=5A153076Numbers k such that Bernoulli number B_{k} has denominator 140100870.at n=29A295599