8128191 has 4 divisors (see below), whose sum is σ = 10837592. Its totient is φ = 5418792.

The previous prime is 8128187. The next prime is 8128213. The reversal of 8128191 is 1918218.

8128191 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 8128191 - 2² = 8128187 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 (8128111) 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, 1354696 + ... + 1354701.

It is an arithmetic number, because the mean of its divisors is an integer number (2709398).

Almost surely, 2^8128191 is an apocalyptic number.

8128191 is a deficient number, since it is larger than the sum of its proper divisors (2709401).

8128191 is a wasteful number, since it uses less digits than its factorization.

8128191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2709400.

The product of its digits is 1152, while the sum is 30.

The square root of 8128191 is about 2850.9982462289. The cubic root of 8128191 is about 201.0626027123.

The spelling of 8128191 in words is "eight million, one hundred twenty-eight thousand, one hundred ninety-one".