22121021221 has 8 divisors (see below), whose sum is σ = 23832123224. Its totient is φ = 20411274240.

The previous prime is 22121021201. The next prime is 22121021249. The reversal of 22121021221 is 12212012122.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 408321 + 22120612900 = 639^2 + 148730^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 22121021221 - 2⁵ = 22121021189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 22121021195 and 22121021204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121021201) 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 7 ways as a sum of consecutive naturals, for example, 304716 + ... + 370261.

It is an arithmetic number, because the mean of its divisors is an integer number (2979015403).

Almost surely, 2^22121021221 is an apocalyptic number.

It is an amenable number.

22121021221 is a deficient number, since it is larger than the sum of its proper divisors (1711102003).

22121021221 is a wasteful number, since it uses less digits than its factorization.

22121021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677511.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 22121021221 its reverse (12212012122), we get a palindrome (34333033343).

Subtracting from 22121021221 its reverse (12212012122), we obtain a palindrome (9909009099).

The spelling of 22121021221 in words is "twenty-two billion, one hundred twenty-one million, twenty-one thousand, two hundred twenty-one".