21301052444 has 72 divisors (see below), whose sum is σ = 44863483392. Its totient is φ = 8814445920.

The previous prime is 21301052387. The next prime is 21301052453. The reversal of 21301052444 is 44425010312.

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, 2833739 + ... + 2841245.

It is an arithmetic number, because the mean of its divisors is an integer number (623103936).

Almost surely, 2^21301052444 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 21301052444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22431741696).

21301052444 is an abundant number, since it is smaller than the sum of its proper divisors (23562430948).

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

21301052444 is a wasteful number, since it uses less digits than its factorization.

21301052444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8023 (or 8014 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

Adding to 21301052444 its reverse (44425010312), we get a palindrome (65726062756).

The spelling of 21301052444 in words is "twenty-one billion, three hundred one million, fifty-two thousand, four hundred forty-four".