12891187 has 2 divisors, whose sum is σ = 12891188. Its totient is φ = 12891186.

The previous prime is 12891173. The next prime is 12891209. The reversal of 12891187 is 78119821.

12891187 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12891187 - 2¹⁹ = 12366899 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12891157) 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, 6445593 + 6445594.

It is an arithmetic number, because the mean of its divisors is an integer number (6445594).

Almost surely, 2^12891187 is an apocalyptic number.

12891187 is a deficient number, since it is larger than the sum of its proper divisors (1).

12891187 is an equidigital number, since it uses as much as digits as its factorization.

12891187 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 12891187 is about 3590.4299185474. The cubic root of 12891187 is about 234.4755893442.

The spelling of 12891187 in words is "twelve million, eight hundred ninety-one thousand, one hundred eighty-seven".