12189871 has 2 divisors, whose sum is σ = 12189872. Its totient is φ = 12189870.

The previous prime is 12189869. The next prime is 12189907. The reversal of 12189871 is 17898121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12189871 - 2¹ = 12189869 is a prime.

Together with 12189869, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 12189871.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12189071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6094935 + 6094936.

It is an arithmetic number, because the mean of its divisors is an integer number (6094936).

Almost surely, 2^12189871 is an apocalyptic number.

12189871 is a deficient number, since it is larger than the sum of its proper divisors (1).

12189871 is an equidigital number, since it uses as much as digits as its factorization.

12189871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 37.

The square root of 12189871 is about 3491.3995761013. The cubic root of 12189871 is about 230.1440244758.

The spelling of 12189871 in words is "twelve million, one hundred eighty-nine thousand, eight hundred seventy-one".