21136638213 has 48 divisors (see below), whose sum is σ = 31204293120. Its totient is φ = 13784601600.

The previous prime is 21136638163. The next prime is 21136638227. The reversal of 21136638213 is 31283663112.

21136638213 is a `hidden beast` number, since 2 + 1 + 1 + 3 + 6 + 638 + 2 + 13 = 666.

It is not a de Polignac number, because 21136638213 - 2²⁴ = 21119860997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21136638253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 43047898 + ... + 43048388.

It is an arithmetic number, because the mean of its divisors is an integer number (650089440).

Almost surely, 2^21136638213 is an apocalyptic number.

It is an amenable number.

21136638213 is a deficient number, since it is larger than the sum of its proper divisors (10067654907).

21136638213 is a wasteful number, since it uses less digits than its factorization.

21136638213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1050 (or 1047 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The spelling of 21136638213 in words is "twenty-one billion, one hundred thirty-six million, six hundred thirty-eight thousand, two hundred thirteen".