221221022112 has 72 divisors (see below), whose sum is σ = 629224648416. Its totient is φ = 73725411456.

The previous prime is 221221022111. The next prime is 221221022131. The reversal of 221221022112 is 211220122122.

It is a happy number.

221221022112 is a `hidden beast` number, since 221 + 2 + 210 + 221 + 12 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (221221022111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1395613 + ... + 1546019.

It is an arithmetic number, because the mean of its divisors is an integer number (8739231228).

Almost surely, 2^221221022112 is an apocalyptic number.

It is an amenable number.

221221022112 is an abundant number, since it is smaller than the sum of its proper divisors (408003626304).

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

221221022112 is a wasteful number, since it uses less digits than its factorization.

221221022112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155530 (or 155519 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221221022112 its reverse (211220122122), we get a palindrome (432441144234).

It can be divided in two parts, 2212210 and 22112, that added together give a palindrome (2234322).

The spelling of 221221022112 in words is "two hundred twenty-one billion, two hundred twenty-one million, twenty-two thousand, one hundred twelve".