21100222120120 has 128 divisors (see below), whose sum is σ = 56607882186240. Its totient is φ = 6976881584640.

The previous prime is 21100222120079. The next prime is 21100222120139. The reversal of 21100222120120 is 2102122200112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21100222120094 and 21100222120103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27145492 + ... + 27911971.

It is an arithmetic number, because the mean of its divisors is an integer number (442249079580).

Almost surely, 2^{21100222120120} is an apocalyptic number.

21100222120120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100222120120 is an abundant number, since it is smaller than the sum of its proper divisors (35507660066120).

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

21100222120120 is a wasteful number, since it uses less digits than its factorization.

21100222120120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55057565 (or 55057561 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21100222120120 its reverse (2102122200112), we get a palindrome (23202344320232).

The spelling of 21100222120120 in words is "twenty-one trillion, one hundred billion, two hundred twenty-two million, one hundred twenty thousand, one hundred twenty".