6439939 has 8 divisors (see below), whose sum is σ = 7051968. Its totient is φ = 5832360.

The previous prime is 6439933. The next prime is 6439949. The reversal of 6439939 is 9399346.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6439939 - 2⁹ = 6439427 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6439895 and 6439904.

It is not an unprimeable number, because it can be changed into a prime (6439933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2424 + ... + 4330.

It is an arithmetic number, because the mean of its divisors is an integer number (881496).

Almost surely, 2^6439939 is an apocalyptic number.

6439939 is a deficient number, since it is larger than the sum of its proper divisors (612029).

6439939 is a wasteful number, since it uses less digits than its factorization.

6439939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2225.

The product of its digits is 157464, while the sum is 43.

The square root of 6439939 is about 2537.7034893777. The cubic root of 6439939 is about 186.0489619436.

The spelling of 6439939 in words is "six million, four hundred thirty-nine thousand, nine hundred thirty-nine".