221022211221 has 64 divisors (see below), whose sum is σ = 394257049600. Its totient is φ = 119546668800.

The previous prime is 221022211133. The next prime is 221022211237. The reversal of 221022211221 is 122112220122.

It is a happy number.

221022211221 is a `hidden beast` number, since 2 + 210 + 22 + 211 + 221 = 666.

It is not a de Polignac number, because 221022211221 - 2⁷ = 221022211093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221022211194 and 221022211203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221022211271) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4178781 + ... + 4231341.

It is an arithmetic number, because the mean of its divisors is an integer number (6160266400).

Almost surely, 2^221022211221 is an apocalyptic number.

221022211221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221022211221 is a deficient number, since it is larger than the sum of its proper divisors (173234838379).

221022211221 is a wasteful number, since it uses less digits than its factorization.

221022211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53767 (or 53761 counting only the distinct ones).

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

Adding to 221022211221 its reverse (122112220122), we get a palindrome (343134431343).

The spelling of 221022211221 in words is "two hundred twenty-one billion, twenty-two million, two hundred eleven thousand, two hundred twenty-one".