12189181 has 2 divisors, whose sum is σ = 12189182. Its totient is φ = 12189180.

The previous prime is 12189179. The next prime is 12189257. The reversal of 12189181 is 18198121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11256025 + 933156 = 3355^2 + 966^2 .

It is a cyclic number.

It is not a de Polignac number, because 12189181 - 2¹ = 12189179 is a prime.

It is a super-2 number, since 2×12189181² = 297152266901522, which contains 22 as substring.

Together with 12189179, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12189161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6094590 + 6094591.

It is an arithmetic number, because the mean of its divisors is an integer number (6094591).

Almost surely, 2^12189181 is an apocalyptic number.

It is an amenable number.

12189181 is a deficient number, since it is larger than the sum of its proper divisors (1).

12189181 is an equidigital number, since it uses as much as digits as its factorization.

12189181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 31.

The square root of 12189181 is about 3491.3007604616. The cubic root of 12189181 is about 230.1396820078.

The spelling of 12189181 in words is "twelve million, one hundred eighty-nine thousand, one hundred eighty-one".