21111021100120 has 32 divisors (see below), whose sum is σ = 54285482829600. Its totient is φ = 7238064377088.

The previous prime is 21111021100111. The next prime is 21111021100133. The reversal of 21111021100120 is 2100112011112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21111021100120.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37698251685 + ... + 37698252244.

It is an arithmetic number, because the mean of its divisors is an integer number (1696421338425).

Almost surely, 2^{21111021100120} is an apocalyptic number.

21111021100120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111021100120 is an abundant number, since it is smaller than the sum of its proper divisors (33174461729480).

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

21111021100120 is a wasteful number, since it uses less digits than its factorization.

21111021100120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75396503947 (or 75396503943 counting only the distinct ones).

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

Adding to 21111021100120 its reverse (2100112011112), we get a palindrome (23211133111232).

The spelling of 21111021100120 in words is "twenty-one trillion, one hundred eleven billion, twenty-one million, one hundred thousand, one hundred twenty".