81745392368 has 40 divisors (see below), whose sum is σ = 167009905920. Its totient is φ = 38653606080.

The previous prime is 81745392359. The next prime is 81745392403. The reversal of 81745392368 is 86329354718.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 61880 + ... + 409047.

It is an arithmetic number, because the mean of its divisors is an integer number (4175247648).

Almost surely, 2^81745392368 is an apocalyptic number.

It is an amenable number.

81745392368 is an abundant number, since it is smaller than the sum of its proper divisors (85264513552).

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

81745392368 is a wasteful number, since it uses less digits than its factorization.

81745392368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471525 (or 471519 counting only the distinct ones).

The product of its digits is 8709120, while the sum is 56.

The spelling of 81745392368 in words is "eighty-one billion, seven hundred forty-five million, three hundred ninety-two thousand, three hundred sixty-eight".