12211021 has 2 divisors, whose sum is σ = 12211022. Its totient is φ = 12211020.

The previous prime is 12211009. The next prime is 12211057. The reversal of 12211021 is 12011221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7502121 + 4708900 = 2739^2 + 2170^2 .

It is a cyclic number.

It is not a de Polignac number, because 12211021 - 2¹⁹ = 11686733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12210989 and 12211007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12211061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6105510 + 6105511.

It is an arithmetic number, because the mean of its divisors is an integer number (6105511).

Almost surely, 2^12211021 is an apocalyptic number.

It is an amenable number.

12211021 is a deficient number, since it is larger than the sum of its proper divisors (1).

12211021 is an equidigital number, since it uses as much as digits as its factorization.

12211021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 12211021 is about 3494.4271347390. The cubic root of 12211021 is about 230.2770511416.

Adding to 12211021 its reverse (12011221), we get a palindrome (24222242).

The spelling of 12211021 in words is "twelve million, two hundred eleven thousand, twenty-one".