21100100112 has 360 divisors, whose sum is σ = 75987516696. Its totient is φ = 5413588992.

The previous prime is 21100100093. The next prime is 21100100143.

It is a happy number.

21100100112 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 5728067856 + 15372032256 = 75684^2 + 123984^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21100100094 and 21100100103.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3390828 + ... + 3397044.

Almost surely, 2^21100100112 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100100112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37993758348).

21100100112 is an abundant number, since it is smaller than the sum of its proper divisors (54887416584).

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

21100100112 is a wasteful number, since it uses less digits than its factorization.

21100100112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6295 (or 6279 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The spelling of 21100100112 in words is "twenty-one billion, one hundred million, one hundred thousand, one hundred twelve".