81858040705084 has 48 divisors (see below), whose sum is σ = 170860237732800. Its totient is φ = 33572537865216.

The previous prime is 81858040705079. The next prime is 81858040705087. The reversal of 81858040705084 is 48050704085818.

It is a Harshad number since it is a multiple of its sum of digits (58).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81858040705087) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 445971939 + ... + 446155450.

It is an arithmetic number, because the mean of its divisors is an integer number (3559588286100).

Almost surely, 2^{81858040705084} is an apocalyptic number.

It is an amenable number.

81858040705084 is an abundant number, since it is smaller than the sum of its proper divisors (89002197027716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81858040705084 is a wasteful number, since it uses less digits than its factorization.

81858040705084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 892127542 (or 892127540 counting only the distinct ones).

The product of its (nonzero) digits is 11468800, while the sum is 58.

The spelling of 81858040705084 in words is "eighty-one trillion, eight hundred fifty-eight billion, forty million, seven hundred five thousand, eighty-four".