21103926508 has 24 divisors (see below), whose sum is σ = 42259309344. Its totient is φ = 9033513600.

The previous prime is 21103926479. The next prime is 21103926509. The reversal of 21103926508 is 80562930112.

It is not an unprimeable number, because it can be changed into a prime (21103926509) by changing a digit.

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, 436033 + ... + 482008.

It is an arithmetic number, because the mean of its divisors is an integer number (1760804556).

Almost surely, 2^21103926508 is an apocalyptic number.

21103926508 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21103926508 is an abundant number, since it is smaller than the sum of its proper divisors (21155382836).

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

21103926508 is a wasteful number, since it uses less digits than its factorization.

21103926508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918873 (or 918871 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The spelling of 21103926508 in words is "twenty-one billion, one hundred three million, nine hundred twenty-six thousand, five hundred eight".