21100112200000 has 168 divisors, whose sum is σ = 52356615759000. Its totient is φ = 8436529920000.

The previous prime is 21100112199997. The next prime is 21100112200019. The reversal of 21100112200000 is 221100112.

It can be written as a sum of positive squares in 12 ways, for example, as 17973326334016 + 3126785865984 = 4239496^2 + 1768272^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a self number, because there is not a number n which added to its sum of digits gives 21100112200000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 509779306 + ... + 509820694.

It is an arithmetic number, because the mean of its divisors is an integer number (311646522375).

Almost surely, 2^{21100112200000} is an apocalyptic number.

21100112200000 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 21100112200000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26178307879500).

21100112200000 is an abundant number, since it is smaller than the sum of its proper divisors (31256503559000).

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

21100112200000 is an frugal number, since it uses more digits than its factorization.

21100112200000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43975 (or 43945 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21100112200000 its reverse (221100112), we get a palindrome (21100333300112).

The spelling of 21100112200000 in words is "twenty-one trillion, one hundred billion, one hundred twelve million, two hundred thousand".