21002112111100 has 18 divisors (see below), whose sum is σ = 45574583281304. Its totient is φ = 8400844844400.

The previous prime is 21002112110977. The next prime is 21002112111173. The reversal of 21002112111100 is 111121120012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105010560456 + ... + 105010560655.

Almost surely, 2^{21002112111100} is an apocalyptic number.

21002112111100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002112111100 is an abundant number, since it is smaller than the sum of its proper divisors (24572471170204).

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

21002112111100 is a wasteful number, since it uses less digits than its factorization.

21002112111100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210021121125 (or 210021121118 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21002112111100 its reverse (111121120012), we get a palindrome (21113233231112).

The spelling of 21002112111100 in words is "twenty-one trillion, two billion, one hundred twelve million, one hundred eleven thousand, one hundred".