1638536013 has 32 divisors (see below), whose sum is σ = 2514758400. Its totient is φ = 1053676800.

The previous prime is 1638535967. The next prime is 1638536017. The reversal of 1638536013 is 3106358361.

It is a happy number.

1638536013 is a `hidden beast` number, since 1 + 638 + 5 + 3 + 6 + 0 + 13 = 666.

It is not a de Polignac number, because 1638536013 - 2⁹ = 1638535501 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638536017) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90208 + ... + 106838.

It is an arithmetic number, because the mean of its divisors is an integer number (78586200).

Almost surely, 2^1638536013 is an apocalyptic number.

It is an amenable number.

1638536013 is a deficient number, since it is larger than the sum of its proper divisors (876222387).

1638536013 is a wasteful number, since it uses less digits than its factorization.

1638536013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16770 (or 16764 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 1638536013 is about 40478.8341358790. The cubic root of 1638536013 is about 1178.9227008091.

The spelling of 1638536013 in words is "one billion, six hundred thirty-eight million, five hundred thirty-six thousand, thirteen".