221221102222221 has 16 divisors (see below), whose sum is σ = 295972287870336. Its totient is φ = 146975339722176.

The previous prime is 221221102222213. The next prime is 221221102222313. The reversal of 221221102222221 is 122222201122122.

It is a happy number.

It is not a de Polignac number, because 221221102222221 - 2³ = 221221102222213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221221102222191 and 221221102222200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221102222121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62716671 + ... + 66150003.

It is an arithmetic number, because the mean of its divisors is an integer number (18498267991896).

Almost surely, 2^{221221102222221} is an apocalyptic number.

It is an amenable number.

221221102222221 is a deficient number, since it is larger than the sum of its proper divisors (74751185648115).

221221102222221 is a wasteful number, since it uses less digits than its factorization.

221221102222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3506932.

The product of its (nonzero) digits is 1024, while the sum is 24.

Adding to 221221102222221 its reverse (122222201122122), we get a palindrome (343443303344343).

The spelling of 221221102222221 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred two million, two hundred twenty-two thousand, two hundred twenty-one".