81858040705204 has 48 divisors (see below), whose sum is σ = 152558683069968. Its totient is φ = 38297810567168.

The previous prime is 81858040705139. The next prime is 81858040705291. The reversal of 81858040705204 is 40250704085818.

It can be written as a sum of positive squares in 8 ways, for example, as 8166460720804 + 73691579984400 = 2857702^2 + 8584380^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 745512132 + ... + 745621924.

It is an arithmetic number, because the mean of its divisors is an integer number (3178305897291).

Almost surely, 2^{81858040705204} is an apocalyptic number.

It is an amenable number.

81858040705204 is a deficient number, since it is larger than the sum of its proper divisors (70700642364764).

81858040705204 is a wasteful number, since it uses less digits than its factorization.

81858040705204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173364 (or 173362 counting only the distinct ones).

The product of its (nonzero) digits is 2867200, while the sum is 52.

The spelling of 81858040705204 in words is "eighty-one trillion, eight hundred fifty-eight billion, forty million, seven hundred five thousand, two hundred four".