21100004432 has 80 divisors (see below), whose sum is σ = 45052064400. Its totient is φ = 9513676800.

The previous prime is 21100004399. The next prime is 21100004437. The reversal of 21100004432 is 23440000112.

It can be written as a sum of positive squares in 8 ways, for example, as 15589020736 + 5510983696 = 124856^2 + 74236^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21100004432.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100004437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1884932 + ... + 1896092.

It is an arithmetic number, because the mean of its divisors is an integer number (563150805).

Almost surely, 2^21100004432 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 21100004432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22526032200).

21100004432 is an abundant number, since it is smaller than the sum of its proper divisors (23952059968).

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

21100004432 is a wasteful number, since it uses less digits than its factorization.

21100004432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11392 (or 11386 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21100004432 its reverse (23440000112), we get a palindrome (44540004544).

The spelling of 21100004432 in words is "twenty-one billion, one hundred million, four thousand, four hundred thirty-two".