81173612361 has 16 divisors (see below), whose sum is σ = 111024745920. Its totient is φ = 52725388800.

The previous prime is 81173612327. The next prime is 81173612371. The reversal of 81173612361 is 16321637118.

It is not a de Polignac number, because 81173612361 - 2¹¹ = 81173610313 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81173612371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 732876 + ... + 836333.

It is an arithmetic number, because the mean of its divisors is an integer number (6939046620).

Almost surely, 2^81173612361 is an apocalyptic number.

It is an amenable number.

81173612361 is a deficient number, since it is larger than the sum of its proper divisors (29851133559).

81173612361 is a wasteful number, since it uses less digits than its factorization.

81173612361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1569656.

The product of its digits is 36288, while the sum is 39.

The spelling of 81173612361 in words is "eighty-one billion, one hundred seventy-three million, six hundred twelve thousand, three hundred sixty-one".