639000389 has 4 divisors (see below), whose sum is σ = 639424800. Its totient is φ = 638575980.

The previous prime is 639000379. The next prime is 639000451. The reversal of 639000389 is 983000936.

It is a happy number.

639000389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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-639000389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639000359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209939 + ... + 212960.

It is an arithmetic number, because the mean of its divisors is an integer number (159856200).

Almost surely, 2^639000389 is an apocalyptic number.

It is an amenable number.

639000389 is a deficient number, since it is larger than the sum of its proper divisors (424411).

639000389 is a wasteful number, since it uses less digits than its factorization.

639000389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424410.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 639000389 is about 25278.4570138290. The cubic root of 639000389 is about 861.3249762591.

The spelling of 639000389 in words is "six hundred thirty-nine million, three hundred eighty-nine", and thus it is an aban number.