21392128808 has 16 divisors (see below), whose sum is σ = 40118064000. Its totient is φ = 10693978416.

The previous prime is 21392128787. The next prime is 21392128837. The reversal of 21392128808 is 80882129312.

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 3 ways as a sum of consecutive naturals, for example, 216728 + ... + 299591.

It is an arithmetic number, because the mean of its divisors is an integer number (2507379000).

Almost surely, 2^21392128808 is an apocalyptic number.

It is an amenable number.

21392128808 is a deficient number, since it is larger than the sum of its proper divisors (18725935192).

21392128808 is a wasteful number, since it uses less digits than its factorization.

21392128808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521504 (or 521500 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 44.

The spelling of 21392128808 in words is "twenty-one billion, three hundred ninety-two million, one hundred twenty-eight thousand, eight hundred eight".