2191191 has 4 divisors (see below), whose sum is σ = 2921592. Its totient is φ = 1460792.

The previous prime is 2191171. The next prime is 2191193. The reversal of 2191191 is 1911912.

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

It is a cyclic number.

It is not a de Polignac number, because 2191191 - 2⁵ = 2191159 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 365196 + ... + 365201.

It is an arithmetic number, because the mean of its divisors is an integer number (730398).

2^2191191 is an apocalyptic number.

2191191 is a deficient number, since it is larger than the sum of its proper divisors (730401).

2191191 is an equidigital number, since it uses as much as digits as its factorization.

2191191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 730400.

The product of its digits is 162, while the sum is 24.

The square root of 2191191 is about 1480.2672056085. The cubic root of 2191191 is about 129.8853229326.

The spelling of 2191191 in words is "two million, one hundred ninety-one thousand, one hundred ninety-one".