2021043091 has 4 divisors (see below), whose sum is σ = 2127413800. Its totient is φ = 1914672384.

The previous prime is 2021043083. The next prime is 2021043103. The reversal of 2021043091 is 1903401202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2021043091 - 2³ = 2021043083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021043001) 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, 53185326 + ... + 53185363.

It is an arithmetic number, because the mean of its divisors is an integer number (531853450).

Almost surely, 2^2021043091 is an apocalyptic number.

2021043091 is a deficient number, since it is larger than the sum of its proper divisors (106370709).

2021043091 is a wasteful number, since it uses less digits than its factorization.

2021043091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106370708.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 2021043091 is about 44956.0128458919. The cubic root of 2021043091 is about 1264.3244146315.

Adding to 2021043091 its reverse (1903401202), we get a palindrome (3924444293).

The spelling of 2021043091 in words is "two billion, twenty-one million, forty-three thousand, ninety-one".