6638366513 has 12 divisors (see below), whose sum is σ = 6963387060. Its totient is φ = 6327922656.

The previous prime is 6638366479. The next prime is 6638366519. The reversal of 6638366513 is 3156638366.

It can be written as a sum of positive squares in 2 ways, for example, as 5915455744 + 722910769 = 76912^2 + 26887^2 .

It is a de Polignac number, because none of the positive numbers 2^k-6638366513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6638366519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 133583 + ... + 176411.

It is an arithmetic number, because the mean of its divisors is an integer number (580282255).

Almost surely, 2^6638366513 is an apocalyptic number.

It is an amenable number.

6638366513 is a deficient number, since it is larger than the sum of its proper divisors (325020547).

6638366513 is a wasteful number, since it uses less digits than its factorization.

6638366513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43168 (or 43145 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 47.

The square root of 6638366513 is about 81476.1714429440. The cubic root of 6638366513 is about 1879.4051340547.

The spelling of 6638366513 in words is "six billion, six hundred thirty-eight million, three hundred sixty-six thousand, five hundred thirteen".