49901

Appears in sequences

• Numbers x such that sigma(x)-x divides x-1, other than prime powers.at n=12A059047
• a(0) = 1; a(n) = half of the a(n-1)-th even nontotient number.at n=12A071598
• Numbers k such that 2^k == 18 (mod k).at n=12A128126
• Partial sums of A006058.at n=6A176527
• Semiprimes p*q with p < q and 2^p (mod q) == 2^q (mod p).at n=38A179839
• Composite numbers which contain their sum of aliquot parts as a substring.at n=18A225417
• Numbers n such that there are a, b with abs(sigma(a) - sigma(b)) = sigma(n) - n and a U b = n, where U is decimal concatenation.at n=25A239563
• Numbers x such that x = concatenate(a, b) and phi(a) + phi(b) = sigma(x) - x.at n=14A254624