21631869528 has 32 divisors (see below), whose sum is σ = 54411460800. Its totient is φ = 7166384928.

The previous prime is 21631869527. The next prime is 21631869557. The reversal of 21631869528 is 82596813612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21631869527) 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 7 ways as a sum of consecutive naturals, for example, 2760898 + ... + 2768721.

It is an arithmetic number, because the mean of its divisors is an integer number (1700358150).

Almost surely, 2^21631869528 is an apocalyptic number.

It is an amenable number.

21631869528 is an abundant number, since it is smaller than the sum of its proper divisors (32779591272).

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

21631869528 is a wasteful number, since it uses less digits than its factorization.

21631869528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5529791 (or 5529787 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 51.

The spelling of 21631869528 in words is "twenty-one billion, six hundred thirty-one million, eight hundred sixty-nine thousand, five hundred twenty-eight".