12158993221 has 2 divisors, whose sum is σ = 12158993222. Its totient is φ = 12158993220.

The previous prime is 12158993179. The next prime is 12158993227. The reversal of 12158993221 is 12239985121.

12158993221 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., 11615450625 + 543542596 = 107775^2 + 23314^2 .

It is a cyclic number.

It is not a de Polignac number, because 12158993221 - 2⁹ = 12158992709 is a prime.

It is a super-2 number, since 2×12158993221² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12158993227) 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, 6079496610 + 6079496611.

It is an arithmetic number, because the mean of its divisors is an integer number (6079496611).

Almost surely, 2^12158993221 is an apocalyptic number.

It is an amenable number.

12158993221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12158993221 is an equidigital number, since it uses as much as digits as its factorization.

12158993221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 43.

The spelling of 12158993221 in words is "twelve billion, one hundred fifty-eight million, nine hundred ninety-three thousand, two hundred twenty-one".