21013360808 has 16 divisors (see below), whose sum is σ = 42981874560. Its totient is φ = 9551527600.

The previous prime is 21013360807. The next prime is 21013360933. The reversal of 21013360808 is 80806331012.

It is a happy number.

It is a super-2 number, since 2×21013360808² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21013360807) 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 3 ways as a sum of consecutive naturals, for example, 119394008 + ... + 119394183.

It is an arithmetic number, because the mean of its divisors is an integer number (2686367160).

Almost surely, 2^21013360808 is an apocalyptic number.

It is an amenable number.

21013360808 is an abundant number, since it is smaller than the sum of its proper divisors (21968513752).

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

21013360808 is a wasteful number, since it uses less digits than its factorization.

21013360808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238788208 (or 238788204 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The spelling of 21013360808 in words is "twenty-one billion, thirteen million, three hundred sixty thousand, eight hundred eight".