2040821 has 4 divisors (see below), whose sum is σ = 2049600. Its totient is φ = 2032044.

The previous prime is 2040803. The next prime is 2040827. The reversal of 2040821 is 1280402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2040821 - 2¹⁰ = 2039797 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2040821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2040827) 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, 4031 + ... + 4508.

It is an arithmetic number, because the mean of its divisors is an integer number (512400).

2^2040821 is an apocalyptic number.

It is an amenable number.

2040821 is a deficient number, since it is larger than the sum of its proper divisors (8779).

2040821 is an equidigital number, since it uses as much as digits as its factorization.

2040821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8778.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2040821 is about 1428.5730642848. The cubic root of 2040821 is about 126.8435256441.

The spelling of 2040821 in words is "two million, forty thousand, eight hundred twenty-one".