21111111122200 has 192 divisors, whose sum is σ = 54096661386720. Its totient is φ = 7597800960000.

The previous prime is 21111111122177. The next prime is 21111111122201. The reversal of 21111111122200 is 222111111112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111111122201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 617032294 + ... + 617066506.

Almost surely, 2^{21111111122200} is an apocalyptic number.

21111111122200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21111111122200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27048330693360).

21111111122200 is an abundant number, since it is smaller than the sum of its proper divisors (32985550264520).

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

21111111122200 is a wasteful number, since it uses less digits than its factorization.

21111111122200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37118 (or 37109 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 21111111122200 its reverse (222111111112), we get a palindrome (21333222233312).

It can be divided in two parts, 211111 and 11122200, that added together give a palindrome (11333311).

The spelling of 21111111122200 in words is "twenty-one trillion, one hundred eleven billion, one hundred eleven million, one hundred twenty-two thousand, two hundred".