6438239949 has 16 divisors (see below), whose sum is σ = 9243339840. Its totient is φ = 3971208960.

The previous prime is 6438239921. The next prime is 6438239957. The reversal of 6438239949 is 9499328346.

It is a happy number.

It is not a de Polignac number, because 6438239949 - 2²³ = 6429851341 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6438239909) 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, 1066822 + ... + 1072839.

It is an arithmetic number, because the mean of its divisors is an integer number (577708740).

Almost surely, 2^6438239949 is an apocalyptic number.

It is an amenable number.

6438239949 is a deficient number, since it is larger than the sum of its proper divisors (2805099891).

6438239949 is a wasteful number, since it uses less digits than its factorization.

6438239949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2139740.

The product of its digits is 10077696, while the sum is 57.

The square root of 6438239949 is about 80238.6437385379. The cubic root of 6438239949 is about 1860.3259872039.

The spelling of 6438239949 in words is "six billion, four hundred thirty-eight million, two hundred thirty-nine thousand, nine hundred forty-nine".