81858040705194 has 64 divisors (see below), whose sum is σ = 176470347876480. Its totient is φ = 25164135152640.

The previous prime is 81858040705139. The next prime is 81858040705291. The reversal of 81858040705194 is 49150704085818.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 706473637 + ... + 706589495.

It is an arithmetic number, because the mean of its divisors is an integer number (2757349185570).

Almost surely, 2^{81858040705194} is an apocalyptic number.

81858040705194 is an abundant number, since it is smaller than the sum of its proper divisors (94612307171286).

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

81858040705194 is a wasteful number, since it uses less digits than its factorization.

81858040705194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124055.

The product of its (nonzero) digits is 12902400, while the sum is 60.

The spelling of 81858040705194 in words is "eighty-one trillion, eight hundred fifty-eight billion, forty million, seven hundred five thousand, one hundred ninety-four".