6639381717 has 16 divisors (see below), whose sum is σ = 9372308160. Its totient is φ = 4169048832.

The previous prime is 6639381701. The next prime is 6639381743. The reversal of 6639381717 is 7171839366.

It is not a de Polignac number, because 6639381717 - 2⁴ = 6639381701 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6639381717.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639381757) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 326788 + ... + 346509.

It is an arithmetic number, because the mean of its divisors is an integer number (585769260).

Almost surely, 2^6639381717 is an apocalyptic number.

It is an amenable number.

6639381717 is a deficient number, since it is larger than the sum of its proper divisors (2732926443).

6639381717 is a wasteful number, since it uses less digits than its factorization.

6639381717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673492.

The product of its digits is 1143072, while the sum is 51.

The square root of 6639381717 is about 81482.4012716857. The cubic root of 6639381717 is about 1879.5009348491.

The spelling of 6639381717 in words is "six billion, six hundred thirty-nine million, three hundred eighty-one thousand, seven hundred seventeen".