12211021021 has 6 divisors (see below), whose sum is σ = 12516116666. Its totient is φ = 11913189600.

The previous prime is 12211020971. The next prime is 12211021037. The reversal of 12211021021 is 12012011221.

It can be written as a sum of positive squares in 3 ways, for example, as 1860196900 + 10350824121 = 43130^2 + 101739^2 .

It is not a de Polignac number, because 12211021021 - 2⁷ = 12211020893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12211020992 and 12211021010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12211021321) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3630390 + ... + 3633751.

Almost surely, 2^12211021021 is an apocalyptic number.

It is an amenable number.

12211021021 is a deficient number, since it is larger than the sum of its proper divisors (305095645).

12211021021 is an frugal number, since it uses more digits than its factorization.

12211021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7264223 (or 7264182 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 12211021021 its reverse (12012011221), we get a palindrome (24223032242).

The spelling of 12211021021 in words is "twelve billion, two hundred eleven million, twenty-one thousand, twenty-one".