81523173358863 has 96 divisors (see below), whose sum is σ = 130934454635520. Its totient is φ = 50087862095040.

The previous prime is 81523173358841. The next prime is 81523173358873. The reversal of 81523173358863 is 36885337132518.

81523173358863 is a `hidden beast` number, since 8 + 1 + 5 + 2 + 3 + 17 + 33 + 588 + 6 + 3 = 666.

It is not a de Polignac number, because 81523173358863 - 2¹² = 81523173354767 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81523173358863.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81523173358873) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2449082806 + ... + 2449116092.

It is an arithmetic number, because the mean of its divisors is an integer number (1363900569120).

Almost surely, 2^{81523173358863} is an apocalyptic number.

81523173358863 is a deficient number, since it is larger than the sum of its proper divisors (49411281276657).

81523173358863 is a wasteful number, since it uses less digits than its factorization.

81523173358863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40162 (or 40137 counting only the distinct ones).

The product of its digits is 87091200, while the sum is 63.

The spelling of 81523173358863 in words is "eighty-one trillion, five hundred twenty-three billion, one hundred seventy-three million, three hundred fifty-eight thousand, eight hundred sixty-three".