21188358653 has 32 divisors (see below), whose sum is σ = 27735644160. Its totient is φ = 15703047360.

The previous prime is 21188358647. The next prime is 21188358679. The reversal of 21188358653 is 35685388112.

It is a happy number.

It is not a de Polignac number, because 21188358653 - 2⁶ = 21188358589 is a prime.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21188358643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78800 + ... + 220422.

It is an arithmetic number, because the mean of its divisors is an integer number (866738880).

Almost surely, 2^21188358653 is an apocalyptic number.

It is an amenable number.

21188358653 is a deficient number, since it is larger than the sum of its proper divisors (6547285507).

21188358653 is a wasteful number, since it uses less digits than its factorization.

21188358653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141737.

The product of its digits is 1382400, while the sum is 50.

The spelling of 21188358653 in words is "twenty-one billion, one hundred eighty-eight million, three hundred fifty-eight thousand, six hundred fifty-three".