2091571 has 4 divisors (see below), whose sum is σ = 2095200. Its totient is φ = 2087944.

The previous prime is 2091553. The next prime is 2091581. The reversal of 2091571 is 1751902.

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 2091571 - 2⁷ = 2091443 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2091521) 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, 736 + ... + 2173.

It is an arithmetic number, because the mean of its divisors is an integer number (523800).

2^2091571 is an apocalyptic number.

2091571 is a deficient number, since it is larger than the sum of its proper divisors (3629).

2091571 is an equidigital number, since it uses as much as digits as its factorization.

2091571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3628.

The product of its (nonzero) digits is 630, while the sum is 25.

The square root of 2091571 is about 1446.2264691258. The cubic root of 2091571 is about 127.8863533914.

It can be divided in two parts, 2091 and 571, that added together give a palindrome (2662).

The spelling of 2091571 in words is "two million, ninety-one thousand, five hundred seventy-one".