12118921 has 2 divisors, whose sum is σ = 12118922. Its totient is φ = 12118920.

The previous prime is 12118891. The next prime is 12118933. The reversal of 12118921 is 12981121.

12118921 is digitally balanced in base 3, 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., 11128896 + 990025 = 3336^2 + 995^2 .

It is a cyclic number.

It is not a de Polignac number, because 12118921 - 2⁷ = 12118793 is a prime.

It is not a weakly prime, because it can be changed into another prime (12118961) 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, 6059460 + 6059461.

It is an arithmetic number, because the mean of its divisors is an integer number (6059461).

Almost surely, 2^12118921 is an apocalyptic number.

It is an amenable number.

12118921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12118921 is an equidigital number, since it uses as much as digits as its factorization.

12118921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 25.

The square root of 12118921 is about 3481.2240663307. The cubic root of 12118921 is about 229.6966448084.

The spelling of 12118921 in words is "twelve million, one hundred eighteen thousand, nine hundred twenty-one".