21102112008 has 32 divisors (see below), whose sum is σ = 58616978400. Its totient is φ = 7034037264.

The previous prime is 21102112007. The next prime is 21102112039. The reversal of 21102112008 is 80021120112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21102112001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48847266 + ... + 48847697.

It is an arithmetic number, because the mean of its divisors is an integer number (1831780575).

Almost surely, 2^21102112008 is an apocalyptic number.

It is an amenable number.

21102112008 is an abundant number, since it is smaller than the sum of its proper divisors (37514866392).

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

21102112008 is a wasteful number, since it uses less digits than its factorization.

21102112008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97694978 (or 97694968 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

The spelling of 21102112008 in words is "twenty-one billion, one hundred two million, one hundred twelve thousand, eight".