12221012221 has 18 divisors (see below), whose sum is σ = 13568700698. Its totient is φ = 10998900000.

The previous prime is 12221012137. The next prime is 12221012227.

It is a happy number.

12221012221 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 3 ways, for example, as 11153683321 + 1067328900 = 105611^2 + 32670^2 .

It is not a de Polignac number, because 12221012221 - 2⁹ = 12221011709 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12221012195 and 12221012204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221012227) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1229371 + ... + 1239271.

Almost surely, 2^12221012221 is an apocalyptic number.

12221012221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12221012221 is a deficient number, since it is larger than the sum of its proper divisors (1347688477).

12221012221 is an equidigital number, since it uses as much as digits as its factorization.

12221012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10125 (or 10013 counting only the distinct ones).

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

It can be divided in two parts, 122210 and 12221, that added together give a palindrome (134431).

The spelling of 12221012221 in words is "twelve billion, two hundred twenty-one million, twelve thousand, two hundred twenty-one".