21525241244 has 48 divisors (see below), whose sum is σ = 41641572000. Its totient is φ = 9672514560.

The previous prime is 21525241229. The next prime is 21525241261. The reversal of 21525241244 is 44214252512.

It is a super-2 number, since 2×21525241244² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21525241244.

It is a congruent number.

It is an unprimeable number.

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, 1053752 + ... + 1073984.

It is an arithmetic number, because the mean of its divisors is an integer number (867532750).

Almost surely, 2^21525241244 is an apocalyptic number.

It is an amenable number.

21525241244 is a deficient number, since it is larger than the sum of its proper divisors (20116330756).

21525241244 is a wasteful number, since it uses less digits than its factorization.

21525241244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20790 (or 20788 counting only the distinct ones).

The product of its digits is 25600, while the sum is 32.

Adding to 21525241244 its reverse (44214252512), we get a palindrome (65739493756).

The spelling of 21525241244 in words is "twenty-one billion, five hundred twenty-five million, two hundred forty-one thousand, two hundred forty-four".