2091395191 has 4 divisors (see below), whose sum is σ = 2158859584. Its totient is φ = 2023930800.

The previous prime is 2091395179. The next prime is 2091395209. The reversal of 2091395191 is 1915931902.

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 2091395191 - 2²¹ = 2089298039 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 (2091395101) 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, 33732150 + ... + 33732211.

It is an arithmetic number, because the mean of its divisors is an integer number (539714896).

Almost surely, 2^2091395191 is an apocalyptic number.

2091395191 is a deficient number, since it is larger than the sum of its proper divisors (67464393).

2091395191 is an equidigital number, since it uses as much as digits as its factorization.

2091395191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67464392.

The product of its (nonzero) digits is 21870, while the sum is 40.

The square root of 2091395191 is about 45731.7744134207. The cubic root of 2091395191 is about 1278.8277008780.

The spelling of 2091395191 in words is "two billion, ninety-one million, three hundred ninety-five thousand, one hundred ninety-one".