81765875875 has 32 divisors (see below), whose sum is σ = 104030469504. Its totient is φ = 64140668800.

The previous prime is 81765875861. The next prime is 81765875899. The reversal of 81765875875 is 57857856718.

It is not a de Polignac number, because 81765875875 - 2⁷ = 81765875747 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81765875875.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17838834 + ... + 17843416.

It is an arithmetic number, because the mean of its divisors is an integer number (3250952172).

Almost surely, 2^81765875875 is an apocalyptic number.

81765875875 is a deficient number, since it is larger than the sum of its proper divisors (22264593629).

81765875875 is a wasteful number, since it uses less digits than its factorization.

81765875875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7344 (or 7334 counting only the distinct ones).

The product of its digits is 131712000, while the sum is 67.

The spelling of 81765875875 in words is "eighty-one billion, seven hundred sixty-five million, eight hundred seventy-five thousand, eight hundred seventy-five".