66584449

Appears in sequences

• Sum of divisors of n, sigma(n) (A000203), is a power of number of divisors of n, d(n) (A000005).at n=25A051281
• Semiprimes that are a product of Mersenne primes.at n=21A144482
• Semiprimes that are a product of distinct Mersenne primes.at n=17A144856
• a(n) is the largest number k such that sigma(k) = 2^n or 0 if no such k exists.at n=26A295043