8666639 has 8 divisors (see below), whose sum is σ = 8988672. Its totient is φ = 8347320.

The previous prime is 8666627. The next prime is 8666681. The reversal of 8666639 is 9366668.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8666639 is a prime.

It is a super-2 number, since 2×8666639² = 150221263112642, which contains 22 as substring.

It is an Ulam number.

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 8666639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8666839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7622 + ... + 8684.

It is an arithmetic number, because the mean of its divisors is an integer number (1123584).

Almost surely, 2^8666639 is an apocalyptic number.

8666639 is a deficient number, since it is larger than the sum of its proper divisors (322033).

8666639 is a wasteful number, since it uses less digits than its factorization.

8666639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1357.

The product of its digits is 279936, while the sum is 44.

The square root of 8666639 is about 2943.9155898225. The cubic root of 8666639 is about 205.4077863496.

The spelling of 8666639 in words is "eight million, six hundred sixty-six thousand, six hundred thirty-nine".