81800488568 has 16 divisors (see below), whose sum is σ = 161448333000. Its totient is φ = 38747599776.

The previous prime is 81800488541. The next prime is 81800488573. The reversal of 81800488568 is 86588400818.

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 3 ways as a sum of consecutive naturals, for example, 269080403 + ... + 269080706.

Almost surely, 2^81800488568 is an apocalyptic number.

It is an amenable number.

81800488568 is a deficient number, since it is larger than the sum of its proper divisors (79647844432).

81800488568 is a wasteful number, since it uses less digits than its factorization.

81800488568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538161134 (or 538161130 counting only the distinct ones).

The product of its (nonzero) digits is 3932160, while the sum is 56.

The spelling of 81800488568 in words is "eighty-one billion, eight hundred million, four hundred eighty-eight thousand, five hundred sixty-eight".