2028021 has 4 divisors (see below), whose sum is σ = 2704032. Its totient is φ = 1352012.

The previous prime is 2028017. The next prime is 2028053. The reversal of 2028021 is 1208202.

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 2028021 - 2² = 2028017 is a prime.

It is a super-2 number, since 2×2028021² = 8225738352882, which contains 22 as substring.

It is a D-number.

2028021 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2028121) 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, 338001 + ... + 338006.

It is an arithmetic number, because the mean of its divisors is an integer number (676008).

2^2028021 is an apocalyptic number.

It is an amenable number.

2028021 is a deficient number, since it is larger than the sum of its proper divisors (676011).

2028021 is an equidigital number, since it uses as much as digits as its factorization.

2028021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676010.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 2028021 is about 1424.0860226826. The cubic root of 2028021 is about 126.5777823643.

It can be divided in two parts, 20280 and 21, that added together give a triangular number (20301 = T₂₀₁).

The spelling of 2028021 in words is "two million, twenty-eight thousand, twenty-one".