2021203421 has 4 divisors (see below), whose sum is σ = 2022907392. Its totient is φ = 2019499452.

The previous prime is 2021203411. The next prime is 2021203427. The reversal of 2021203421 is 1243021202.

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 2021203421 - 2²² = 2017009117 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 2021203421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021203427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850205 + ... + 852578.

It is an arithmetic number, because the mean of its divisors is an integer number (505726848).

Almost surely, 2^2021203421 is an apocalyptic number.

It is an amenable number.

2021203421 is a deficient number, since it is larger than the sum of its proper divisors (1703971).

2021203421 is a wasteful number, since it uses less digits than its factorization.

2021203421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1703970.

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

The square root of 2021203421 is about 44957.7959980246. The cubic root of 2021203421 is about 1264.3578468353.

Adding to 2021203421 its reverse (1243021202), we get a palindrome (3264224623).

The spelling of 2021203421 in words is "two billion, twenty-one million, two hundred three thousand, four hundred twenty-one".