6561111516005 has 16 divisors (see below), whose sum is σ = 7965269815104. Its totient is φ = 5187825135360.

The previous prime is 6561111515957. The next prime is 6561111516013. The reversal of 6561111516005 is 5006151111656.

It is a happy number.

6561111516005 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6561111516005 - 2¹² = 6561111511909 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6561111516005.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13929731 + ... + 14393040.

It is an arithmetic number, because the mean of its divisors is an integer number (497829363444).

Almost surely, 2^{6561111516005} is an apocalyptic number.

It is an amenable number.

6561111516005 is a deficient number, since it is larger than the sum of its proper divisors (1404158299099).

6561111516005 is a wasteful number, since it uses less digits than its factorization.

6561111516005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28323316.

The product of its (nonzero) digits is 27000, while the sum is 38.

The spelling of 6561111516005 in words is "six trillion, five hundred sixty-one billion, one hundred eleven million, five hundred sixteen thousand, five".