221021112 has 64 divisors (see below), whose sum is σ = 597411360. Its totient is φ = 67737600.

The previous prime is 221021111. The next prime is 221021137. The reversal of 221021112 is 211120122.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021111) 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 15 ways as a sum of consecutive naturals, for example, 86412 + ... + 88932.

Almost surely, 2^221021112 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 221021112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (298705680).

221021112 is an abundant number, since it is smaller than the sum of its proper divisors (376390248).

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

221021112 is a wasteful number, since it uses less digits than its factorization.

221021112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2824 (or 2820 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 221021112 is about 14866.7788037624. The cubic root of 221021112 is about 604.6136111694.

Adding to 221021112 its reverse (211120122), we get a palindrome (432141234).

The spelling of 221021112 in words is "two hundred twenty-one million, twenty-one thousand, one hundred twelve".