12215788861 has 2 divisors, whose sum is σ = 12215788862. Its totient is φ = 12215788860.

The previous prime is 12215788843. The next prime is 12215788867. The reversal of 12215788861 is 16888751221.

It is a happy number.

12215788861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11150092836 + 1065696025 = 105594^2 + 32645^2 .

It is an emirp because it is prime and its reverse (16888751221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12215788861 - 2¹¹ = 12215786813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12215788867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6107894430 + 6107894431.

It is an arithmetic number, because the mean of its divisors is an integer number (6107894431).

Almost surely, 2^12215788861 is an apocalyptic number.

It is an amenable number.

12215788861 is a deficient number, since it is larger than the sum of its proper divisors (1).

12215788861 is an equidigital number, since it uses as much as digits as its factorization.

12215788861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 430080, while the sum is 49.

The spelling of 12215788861 in words is "twelve billion, two hundred fifteen million, seven hundred eighty-eight thousand, eight hundred sixty-one".