12138191 has 4 divisors (see below), whose sum is σ = 13071912. Its totient is φ = 11204472.

The previous prime is 12138163. The next prime is 12138193. The reversal of 12138191 is 19183121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19183121 = 41 ⋅467881.

It is a cyclic number.

It is not a de Polignac number, because 12138191 - 2⁶ = 12138127 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12138191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12138193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 466841 + ... + 466866.

It is an arithmetic number, because the mean of its divisors is an integer number (3267978).

Almost surely, 2^12138191 is an apocalyptic number.

12138191 is a deficient number, since it is larger than the sum of its proper divisors (933721).

12138191 is an equidigital number, since it uses as much as digits as its factorization.

12138191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 933720.

The product of its digits is 432, while the sum is 26.

The square root of 12138191 is about 3483.9906716293. The cubic root of 12138191 is about 229.8183253439.

The spelling of 12138191 in words is "twelve million, one hundred thirty-eight thousand, one hundred ninety-one".