153003540480
domain: N
Appears in sequences
- Multiply-perfect numbers: n divides sigma(n).at n=25A007691
- 4-perfect (quadruply-perfect or sous-triple) numbers: sum of divisors of n is 4n.at n=9A027687
- Multiply perfect numbers whose average divisor is an integer and divides the number itself.at n=9A046985
- Intersection of A046985 and A033950: multiply perfect, refactorable numbers with integer average divisor dividing the number.at n=6A047728
- Numbers m such that m = sigma(abs(k)) - 3k, where k = sigma(m) - 3m.at n=17A069146
- Numbers k such that sigma(k)/k, sigma_3(k)/k and sigma_5(k)/k are all integers.at n=16A076231
- Numbers k such that sigma(k)/k and sigma_3(k)/k are both integers.at n=19A076233
- Numbers k such that sigma(k)/k, sigma_3(k)/k, sigma_5(k)/k and sigma_7(k)/k are all integers.at n=13A076234
- Numbers k such that there is a proper divisor d of k satisfying sigma(d)=k.at n=20A081756
- Multiply perfect numbers k such that sigma(k)/k > 2.at n=17A166069
- Numbers m such that k(m) = m/tau(m) - sigma(m)/m is an integer.at n=10A245778
- Refactorable multiply-perfect numbers.at n=6A245782
- Numbers n such that k(n) = (n/tau(n) + sigma(n)/n) is an integer.at n=8A245786
- Sum of divisors of the multiply-perfect numbers.at n=22A307741
- Multi-perfect numbers m from A007691 such that m*(m-tau(m))/sigma(m) is an integer h, where k-tau(k) is the number of nondivisors of k (A049820) and sigma(k) is the sum of the divisors of k (A000203).at n=19A325023
- Numbers that are multi-perfect (A007691) and simultaneously harmonic (A001599).at n=21A325025
- Numbers k for which gcd(2k, sigma(k)) = 2k.at n=16A325637
- Multiply-perfect numbers (A007691) that are arithmetic (A003601).at n=9A331724
- Numbers m such that g(m) = (m * tau(m) / sigma(m)), h(m) = (m * sigma(m)) / tau(m) and k(m) = (tau(m) * sigma(m)) / m are all integers.at n=19A333639
- Numbers whose abundancy index is a power of 2.at n=17A336702