868188639 has 8 divisors (see below), whose sum is σ = 1173889152. Its totient is φ = 570640280.

The previous prime is 868188577. The next prime is 868188719. The reversal of 868188639 is 936881868.

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-868188639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (868189639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2037789 + ... + 2038214.

It is an arithmetic number, because the mean of its divisors is an integer number (146736144).

Almost surely, 2^868188639 is an apocalyptic number.

868188639 is a deficient number, since it is larger than the sum of its proper divisors (305700513).

868188639 is a wasteful number, since it uses less digits than its factorization.

868188639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4076077.

The product of its digits is 3981312, while the sum is 57.

The square root of 868188639 is about 29465.0409638269. The cubic root of 868188639 is about 953.9772825746.

The spelling of 868188639 in words is "eight hundred sixty-eight million, one hundred eighty-eight thousand, six hundred thirty-nine".