2121304121 has 4 divisors (see below), whose sum is σ = 2125376244. Its totient is φ = 2117232000.

The previous prime is 2121304061. The next prime is 2121304169. The reversal of 2121304121 is 1214031212.

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 1380865600 + 740438521 = 37160^2 + 27211^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121304121 - 2¹⁰ = 2121303097 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 2121304121.

It is not an unprimeable number, because it can be changed into a prime (2121304181) 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, 2035280 + ... + 2036321.

It is an arithmetic number, because the mean of its divisors is an integer number (531344061).

Almost surely, 2^2121304121 is an apocalyptic number.

It is an amenable number.

2121304121 is a deficient number, since it is larger than the sum of its proper divisors (4072123).

2121304121 is an equidigital number, since it uses as much as digits as its factorization.

2121304121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4072122.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 2121304121 is about 46057.6174047247. The cubic root of 2121304121 is about 1284.8950180451.

Adding to 2121304121 its reverse (1214031212), we get a palindrome (3335335333).

The spelling of 2121304121 in words is "two billion, one hundred twenty-one million, three hundred four thousand, one hundred twenty-one".