2021591 has 16 divisors (see below), whose sum is σ = 2421888. Its totient is φ = 1663200.

The previous prime is 2021573. The next prime is 2021597. The reversal of 2021591 is 1951202.

It is not a de Polignac number, because 2021591 - 2⁶ = 2021527 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 (2021597) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9476 + ... + 9686.

It is an arithmetic number, because the mean of its divisors is an integer number (151368).

2^2021591 is an apocalyptic number.

2021591 is a deficient number, since it is larger than the sum of its proper divisors (400297).

2021591 is a wasteful number, since it uses less digits than its factorization.

2021591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 2021591 is about 1421.8266420348. The cubic root of 2021591 is about 126.4438657971.

Adding to 2021591 its reverse (1951202), we get a palindrome (3972793).

The spelling of 2021591 in words is "two million, twenty-one thousand, five hundred ninety-one".