21221011232 has 96 divisors (see below), whose sum is σ = 46120233600. Its totient is φ = 9571903488.

The previous prime is 21221011181. The next prime is 21221011241. The reversal of 21221011232 is 23211012212.

It is a self number, because there is not a number n which added to its sum of digits gives 21221011232.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1278893 + ... + 1295379.

It is an arithmetic number, because the mean of its divisors is an integer number (480419100).

Almost surely, 2^21221011232 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 21221011232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23060116800).

21221011232 is an abundant number, since it is smaller than the sum of its proper divisors (24899222368).

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

21221011232 is a wasteful number, since it uses less digits than its factorization.

21221011232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16618 (or 16610 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21221011232 its reverse (23211012212), we get a palindrome (44432023444).

The spelling of 21221011232 in words is "twenty-one billion, two hundred twenty-one million, eleven thousand, two hundred thirty-two".