81604576375 has 16 divisors (see below), whose sum is σ = 116391442752. Its totient is φ = 55957423200.

The previous prime is 81604576373. The next prime is 81604576379. The reversal of 81604576375 is 57367540618.

It is a happy number.

It is not a de Polignac number, because 81604576375 - 2¹ = 81604576373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81604576373) 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, 46630312 + ... + 46632061.

It is an arithmetic number, because the mean of its divisors is an integer number (7274465172).

Almost surely, 2^81604576375 is an apocalyptic number.

81604576375 is a deficient number, since it is larger than the sum of its proper divisors (34786866377).

81604576375 is an equidigital number, since it uses as much as digits as its factorization.

81604576375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93262395 (or 93262385 counting only the distinct ones).

The product of its (nonzero) digits is 4233600, while the sum is 52.

The spelling of 81604576375 in words is "eighty-one billion, six hundred four million, five hundred seventy-six thousand, three hundred seventy-five".