81689642675 has 12 divisors (see below), whose sum is σ = 101303702160. Its totient is φ = 65346201120.

The previous prime is 81689642659. The next prime is 81689642737. The reversal of 81689642675 is 57624698618.

It is not a de Polignac number, because 81689642675 - 2⁴ = 81689642659 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 178706 + ... + 441944.

It is an arithmetic number, because the mean of its divisors is an integer number (8441975180).

Almost surely, 2^81689642675 is an apocalyptic number.

81689642675 is a deficient number, since it is larger than the sum of its proper divisors (19614059485).

81689642675 is a wasteful number, since it uses less digits than its factorization.

81689642675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275662 (or 275657 counting only the distinct ones).

The product of its digits is 34836480, while the sum is 62.

The spelling of 81689642675 in words is "eighty-one billion, six hundred eighty-nine million, six hundred forty-two thousand, six hundred seventy-five".