81696523089 has 16 divisors (see below), whose sum is σ = 113738256000. Its totient is φ = 52062633216.

The previous prime is 81696523067. The next prime is 81696523091. The reversal of 81696523089 is 98032569618.

It is not a de Polignac number, because 81696523089 - 2⁹ = 81696522577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81696523009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 275304 + ... + 489065.

It is an arithmetic number, because the mean of its divisors is an integer number (7108641000).

Almost surely, 2^81696523089 is an apocalyptic number.

It is an amenable number.

81696523089 is a deficient number, since it is larger than the sum of its proper divisors (32041732911).

81696523089 is a wasteful number, since it uses less digits than its factorization.

81696523089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765944.

The product of its (nonzero) digits is 5598720, while the sum is 57.

The spelling of 81696523089 in words is "eighty-one billion, six hundred ninety-six million, five hundred twenty-three thousand, eighty-nine".