6638039 has 4 divisors (see below), whose sum is σ = 6792456. Its totient is φ = 6483624.

The previous prime is 6638029. The next prime is 6638057. The reversal of 6638039 is 9308366.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6638039 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6638029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77144 + ... + 77229.

It is an arithmetic number, because the mean of its divisors is an integer number (1698114).

Almost surely, 2^6638039 is an apocalyptic number.

6638039 is a deficient number, since it is larger than the sum of its proper divisors (154417).

6638039 is a wasteful number, since it uses less digits than its factorization.

6638039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154416.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 6638039 is about 2576.4392094517. The cubic root of 6638039 is about 187.9374225862.

The spelling of 6638039 in words is "six million, six hundred thirty-eight thousand, thirty-nine".