21100110102 has 96 divisors (see below), whose sum is σ = 47683883520. Its totient is φ = 6737290560.

The previous prime is 21100110091. The next prime is 21100110107. The reversal of 21100110102 is 20101100112.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100110107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 23161027 + ... + 23161937.

It is an arithmetic number, because the mean of its divisors is an integer number (496707120).

Almost surely, 2^21100110102 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100110102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23841941760).

21100110102 is an abundant number, since it is smaller than the sum of its proper divisors (26583773418).

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

21100110102 is a wasteful number, since it uses less digits than its factorization.

21100110102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1458 (or 1455 counting only the distinct ones).

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

Adding to 21100110102 its reverse (20101100112), we get a palindrome (41201210214).

The spelling of 21100110102 in words is "twenty-one billion, one hundred million, one hundred ten thousand, one hundred two".