12731191 has 4 divisors (see below), whose sum is σ = 13888584. Its totient is φ = 11573800.

The previous prime is 12731189. The next prime is 12731227. The reversal of 12731191 is 19113721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19113721 = 11 ⋅1737611.

It is a cyclic number.

It is not a de Polignac number, because 12731191 - 2¹ = 12731189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12731161) 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 in 3 ways as a sum of consecutive naturals, for example, 578680 + ... + 578701.

It is an arithmetic number, because the mean of its divisors is an integer number (3472146).

Almost surely, 2^12731191 is an apocalyptic number.

12731191 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12731191 is a deficient number, since it is larger than the sum of its proper divisors (1157393).

12731191 is a wasteful number, since it uses less digits than its factorization.

12731191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1157392.

The product of its digits is 378, while the sum is 25.

The square root of 12731191 is about 3568.0794553933. The cubic root of 12731191 is about 233.5015016708.

The spelling of 12731191 in words is "twelve million, seven hundred thirty-one thousand, one hundred ninety-one".