639832389 has 16 divisors (see below), whose sum is σ = 997658112. Its totient is φ = 357115248.

The previous prime is 639832387. The next prime is 639832399. The reversal of 639832389 is 983238936.

It is not a de Polignac number, because 639832389 - 2¹ = 639832387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639832381) 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 15 ways as a sum of consecutive naturals, for example, 353379 + ... + 355184.

It is an arithmetic number, because the mean of its divisors is an integer number (62353632).

Almost surely, 2^639832389 is an apocalyptic number.

It is an amenable number.

639832389 is a deficient number, since it is larger than the sum of its proper divisors (357825723).

639832389 is a wasteful number, since it uses less digits than its factorization.

639832389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708616.

The product of its digits is 1679616, while the sum is 51.

The square root of 639832389 is about 25294.9083611702. The cubic root of 639832389 is about 861.6986388292.

The spelling of 639832389 in words is "six hundred thirty-nine million, eight hundred thirty-two thousand, three hundred eighty-nine".