21391358826 has 16 divisors (see below), whose sum is σ = 43324272000. Its totient is φ = 7040193888.

The previous prime is 21391358809. The next prime is 21391358837. The reversal of 21391358826 is 62885319312.

21391358826 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 22564251 + ... + 22565198.

It is an arithmetic number, because the mean of its divisors is an integer number (2707767000).

Almost surely, 2^21391358826 is an apocalyptic number.

21391358826 is an abundant number, since it is smaller than the sum of its proper divisors (21932913174).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21391358826 is a wasteful number, since it uses less digits than its factorization.

21391358826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45129533.

The product of its digits is 622080, while the sum is 48.

The spelling of 21391358826 in words is "twenty-one billion, three hundred ninety-one million, three hundred fifty-eight thousand, eight hundred twenty-six".