21103516868 has 12 divisors (see below), whose sum is σ = 42207033792. Its totient is φ = 9044364360.

The previous prime is 21103516849. The next prime is 21103516913. The reversal of 21103516868 is 86861530112.

21103516868 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376848488 + ... + 376848543.

It is an arithmetic number, because the mean of its divisors is an integer number (3517252816).

Almost surely, 2^21103516868 is an apocalyptic number.

21103516868 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21103516868 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21103516868 is a wasteful number, since it uses less digits than its factorization.

21103516868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 753697042 (or 753697040 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 41.

The spelling of 21103516868 in words is "twenty-one billion, one hundred three million, five hundred sixteen thousand, eight hundred sixty-eight".