518666803200
domain: N
Appears in sequences
- 5-multiperfect numbers.at n=2A046060
- Numbers n such that sigma(n) / n is prime.at n=15A065997
- Multiply perfect numbers k for which the quotient sigma_3(k)/k = A001158(k)/k is nonintegral.at n=6A088844
- Multiperfect numbers sigma(n) = k*n, which are divisible by the sum of their prime factors without repetition.at n=6A114887
- Multiply perfect numbers k such that sigma(k)/k > 2.at n=19A166069
- Numbers m such that k(m) = m/tau(m) - sigma(m)/m is an integer.at n=12A245778
- Refactorable multiply-perfect numbers.at n=8A245782
- Numbers n such that k(n) = (n/tau(n) + sigma(n)/n) is an integer.at n=10A245786
- Multiply-perfect numbers m from A007691 such that m*(m-tau(m))/sigma(m) is not an integer where k-tau(k) is the number of the non-divisors of k (A049820) and sigma(k) is the sum of the divisors of k (A000203).at n=6A325024
- Multi-perfect numbers from A007691 that are not harmonic (A001599).at n=4A325026
- Multiply-perfect numbers (A007691) that are arithmetic (A003601).at n=11A331724
- Multiply-perfect numbers k that do not have a divisor d such that sigma(d)*d = k.at n=8A348032
- Multiply-perfect numbers that are the sum of the divisors of some number.at n=26A354073
- Multiperfect numbers k for which gcd(k,A003961(k))*gcd(sigma(k),A276086(k)) is not equal to gcd(k,A276086(k))*gcd(sigma(k),A003961(k)), where A003961(n) is fully multiplicative with a(prime(i)) = prime(i+1), and A276086 is the primorial base exp-function.at n=6A379492