18967

Appears in sequences

• Numbers k such that sigma(phi(sigma(k))) = sigma(k).at n=16A066471
• Numbers k such that k!! + 2^9 is prime.at n=14A076196
• a(n) is the number of digits in the decimal representation of the smallest power of n that contains nine consecutive identical digits.at n=12A217184
• Odd semiprimes k = p*q such that k = A325820(p,q), with p, q primes > 3, and A325820 is the carryless base-3 multiplication.at n=45A391331