12805191 has 24 divisors (see below), whose sum is σ = 21232640. Its totient is φ = 7284816.

The previous prime is 12805187. The next prime is 12805193. The reversal of 12805191 is 19150821.

It is not a de Polignac number, because 12805191 - 2² = 12805187 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 (12805193) 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 23 ways as a sum of consecutive naturals, for example, 27426 + ... + 27888.

Almost surely, 2^12805191 is an apocalyptic number.

12805191 is a deficient number, since it is larger than the sum of its proper divisors (8427449).

12805191 is a wasteful number, since it uses less digits than its factorization.

12805191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 915 (or 912 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 12805191 is about 3578.4341547666. The cubic root of 12805191 is about 233.9530368168.

It can be divided in two parts, 12805 and 191, that added together give a square (12996 = 114²).

The spelling of 12805191 in words is "twelve million, eight hundred five thousand, one hundred ninety-one".