8720021310

Appears in sequences

• Smallest p for which there are exactly n primitive Pythagorean triangles with perimeter p; i.e., smallest p such that A070109(p) = n.at n=17A078928
• Smallest number that has exactly n distinct prime factors and ends with the digits of n.at n=9A109665
• Numbers k such that sigma(k) = phi(k)*(sum of the digits of k).at n=19A140173
• Products of 10 distinct primes (squarefree 10-almost primes).at n=3A281222
• a(n) is the smallest number k such that psi(k) = n*phi(k) where psi(k) is Dedekind psi function (A001615) and phi(k) is Euler totient function (A000010), or 0 if no such k exists.at n=23A291051
• a(n) is the smallest k such that psi(k) and phi(k) have same distinct prime factors when k is the product of n distinct primes (psi(k) = A001615(k) and phi(k) = A000010(k)), or 0 if no such k exists.at n=9A291138
• Numbers whose unitary divisors have a mean unitary abundancy index that is larger than 2.at n=6A374785