21112100021100 has 144 divisors (see below), whose sum is σ = 66639701036160. Its totient is φ = 5117913100800.

The previous prime is 21112100021063. The next prime is 21112100021107. The reversal of 21112100021100 is 112000121112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21112100021107) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 117895431 + ... + 118074369.

It is an arithmetic number, because the mean of its divisors is an integer number (462775701640).

Almost surely, 2^{21112100021100} is an apocalyptic number.

21112100021100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112100021100 is an abundant number, since it is smaller than the sum of its proper divisors (45527601015060).

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

21112100021100 is a wasteful number, since it uses less digits than its factorization.

21112100021100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214720 (or 214713 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21112100021100 its reverse (112000121112), we get a palindrome (21224100142212).

The spelling of 21112100021100 in words is "twenty-one trillion, one hundred twelve billion, one hundred million, twenty-one thousand, one hundred".