8666371681 has 4 divisors (see below), whose sum is σ = 9454223664. Its totient is φ = 7878519700.

The previous prime is 8666371663. The next prime is 8666371697. The reversal of 8666371681 is 1861736668.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8666371681 is a prime.

It is a super-2 number, since 2×8666371681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8666371621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 393925975 + ... + 393925996.

It is an arithmetic number, because the mean of its divisors is an integer number (2363555916).

Almost surely, 2^8666371681 is an apocalyptic number.

It is an amenable number.

8666371681 is a deficient number, since it is larger than the sum of its proper divisors (787851983).

8666371681 is a wasteful number, since it uses less digits than its factorization.

8666371681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787851982.

The product of its digits is 1741824, while the sum is 52.

The square root of 8666371681 is about 93093.3492844682. The cubic root of 8666371681 is about 2054.0567442094.

The spelling of 8666371681 in words is "eight billion, six hundred sixty-six million, three hundred seventy-one thousand, six hundred eighty-one".