2104004221021 has 4 divisors (see below), whose sum is σ = 2105785766844. Its totient is φ = 2102222675200.

The previous prime is 2104004221019. The next prime is 2104004221051. The reversal of 2104004221021 is 1201224004012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1330299264996 + 773704956025 = 1153386^2 + 879605^2 .

It is a cyclic number.

It is not a de Polignac number, because 2104004221021 - 2¹ = 2104004221019 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 2104004221021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2104004221001) 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, 890771140 + ... + 890773501.

It is an arithmetic number, because the mean of its divisors is an integer number (526446441711).

Almost surely, 2^{2104004221021} is an apocalyptic number.

It is an amenable number.

2104004221021 is a deficient number, since it is larger than the sum of its proper divisors (1781545823).

2104004221021 is a wasteful number, since it uses less digits than its factorization.

2104004221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781545822.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 2104004221021 its reverse (1201224004012), we get a palindrome (3305228225033).

The spelling of 2104004221021 in words is "two trillion, one hundred four billion, four million, two hundred twenty-one thousand, twenty-one".