2021243021 has 4 divisors (see below), whose sum is σ = 2309992032. Its totient is φ = 1732494012.

The previous prime is 2021243017. The next prime is 2021243039. The reversal of 2021243021 is 1203421202.

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 2021243021 - 2² = 2021243017 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 (2021203021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144374495 + ... + 144374508.

It is an arithmetic number, because the mean of its divisors is an integer number (577498008).

Almost surely, 2^2021243021 is an apocalyptic number.

It is an amenable number.

2021243021 is a deficient number, since it is larger than the sum of its proper divisors (288749011).

2021243021 is an equidigital number, since it uses as much as digits as its factorization.

2021243021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288749010.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 2021243021 is about 44958.2364089162. The cubic root of 2021243021 is about 1264.3661040025.

Adding to 2021243021 its reverse (1203421202), we get a palindrome (3224664223).

The spelling of 2021243021 in words is "two billion, twenty-one million, two hundred forty-three thousand, twenty-one".