21221021112 has 96 divisors (see below), whose sum is σ = 56911067280. Its totient is φ = 6591352320.

The previous prime is 21221021021. The next prime is 21221021113. The reversal of 21221021112 is 21112012212.

It is a junction number, because it is equal to n+sod(n) for n = 21221021091 and 21221021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221021113) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 508428 + ... + 548580.

Almost surely, 2^21221021112 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 21221021112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28455533640).

21221021112 is an abundant number, since it is smaller than the sum of its proper divisors (35690046168).

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

21221021112 is a wasteful number, since it uses less digits than its factorization.

21221021112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40261 (or 40238 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21221021112 its reverse (21112012212), we get a palindrome (42333033324).

The spelling of 21221021112 in words is "twenty-one billion, two hundred twenty-one million, twenty-one thousand, one hundred twelve".