21121022100200 has 96 divisors (see below), whose sum is σ = 53586550062720. Its totient is φ = 7678083840000.

The previous prime is 21121022100163. The next prime is 21121022100203. The reversal of 21121022100200 is 200122012112.

It is not an unprimeable number, because it can be changed into a prime (21121022100203) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5965985 + ... + 8822415.

It is an arithmetic number, because the mean of its divisors is an integer number (558193229820).

Almost surely, 2^{21121022100200} is an apocalyptic number.

21121022100200 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 21121022100200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26793275031360).

21121022100200 is an abundant number, since it is smaller than the sum of its proper divisors (32465527962520).

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

21121022100200 is a wasteful number, since it uses less digits than its factorization.

21121022100200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2859819 (or 2859810 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21121022100200 its reverse (200122012112), we get a palindrome (21321144112312).

The spelling of 21121022100200 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-two million, one hundred thousand, two hundred".