2091591 has 12 divisors (see below), whose sum is σ = 3035032. Its totient is φ = 1388016.

The previous prime is 2091587. The next prime is 2091599. The reversal of 2091591 is 1951902.

It is a happy number.

It is not a de Polignac number, because 2091591 - 2² = 2091587 is a prime.

It is a super-2 number, since 2×2091591² = 8749505822562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2091599) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2385 + ... + 3141.

2^2091591 is an apocalyptic number.

2091591 is a deficient number, since it is larger than the sum of its proper divisors (943441).

2091591 is a wasteful number, since it uses less digits than its factorization.

2091591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1070 (or 1067 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 2091591 is about 1446.2333836556. The cubic root of 2091591 is about 127.8867610147.

The spelling of 2091591 in words is "two million, ninety-one thousand, five hundred ninety-one".