12240021221 has 2 divisors, whose sum is σ = 12240021222. Its totient is φ = 12240021220.

The previous prime is 12240021203. The next prime is 12240021263. The reversal of 12240021221 is 12212004221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8508033121 + 3731988100 = 92239^2 + 61090^2 .

It is an emirp because it is prime and its reverse (12212004221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12240021221 - 2¹⁰ = 12240020197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12240021221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12240026221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6120010610 + 6120010611.

It is an arithmetic number, because the mean of its divisors is an integer number (6120010611).

Almost surely, 2^12240021221 is an apocalyptic number.

It is an amenable number.

12240021221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12240021221 is an equidigital number, since it uses as much as digits as its factorization.

12240021221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 12240021221 its reverse (12212004221), we get a palindrome (24452025442).

The spelling of 12240021221 in words is "twelve billion, two hundred forty million, twenty-one thousand, two hundred twenty-one".