85666808677 has 4 divisors (see below), whose sum is σ = 85794100300. Its totient is φ = 85539517056.

The previous prime is 85666808651. The next prime is 85666808683. The reversal of 85666808677 is 77680866658.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77680866658 = 2 ⋅38840433329.

It can be written as a sum of positive squares in 2 ways, for example, as 19891999521 + 65774809156 = 141039^2 + 256466^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85666808677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85666808627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63644802 + ... + 63646147.

It is an arithmetic number, because the mean of its divisors is an integer number (21448525075).

Almost surely, 2^85666808677 is an apocalyptic number.

It is an amenable number.

85666808677 is a deficient number, since it is larger than the sum of its proper divisors (127291623).

85666808677 is a wasteful number, since it uses less digits than its factorization.

85666808677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127291622.

The product of its (nonzero) digits is 162570240, while the sum is 67.

The spelling of 85666808677 in words is "eighty-five billion, six hundred sixty-six million, eight hundred eight thousand, six hundred seventy-seven".