2708640

Appears in sequences

• sigma(n) is an additive inverse of n modulo phi(n).at n=32A235989
• Numbers k for which k * gcd(sigma(k), A276086(k)) is equal to sigma(k) * gcd(k, A276086(k)), where A276086 is the primorial base exp-function, and sigma gives the sum of divisors of its argument.at n=19A351458