81167731232 has 24 divisors (see below), whose sum is σ = 182627395776. Its totient is φ = 34786170432.

The previous prime is 81167731223. The next prime is 81167731261. The reversal of 81167731232 is 23213776118.

It is a self number, because there is not a number n which added to its sum of digits gives 81167731232.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 181177748 + ... + 181178195.

It is an arithmetic number, because the mean of its divisors is an integer number (7609474824).

Almost surely, 2^81167731232 is an apocalyptic number.

It is an amenable number.

81167731232 is an abundant number, since it is smaller than the sum of its proper divisors (101459664544).

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

81167731232 is a wasteful number, since it uses less digits than its factorization.

81167731232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362355960 (or 362355952 counting only the distinct ones).

The product of its digits is 84672, while the sum is 41.

The spelling of 81167731232 in words is "eighty-one billion, one hundred sixty-seven million, seven hundred thirty-one thousand, two hundred thirty-two".