2123343120421 has 4 divisors (see below), whose sum is σ = 2123346037644. Its totient is φ = 2123340203200.

The previous prime is 2123343120413. The next prime is 2123343120427. The reversal of 2123343120421 is 1240213433212.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1790541048321 + 332802072100 = 1338111^2 + 576890^2 .

It is a cyclic number.

It is not a de Polignac number, because 2123343120421 - 2³ = 2123343120413 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 2123343120421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2123343120427) 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, 632061 + ... + 2155501.

It is an arithmetic number, because the mean of its divisors is an integer number (530836509411).

Almost surely, 2^{2123343120421} is an apocalyptic number.

It is an amenable number.

2123343120421 is a deficient number, since it is larger than the sum of its proper divisors (2917223).

2123343120421 is a wasteful number, since it uses less digits than its factorization.

2123343120421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2917222.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 2123343120421 its reverse (1240213433212), we get a palindrome (3363556553633).

The spelling of 2123343120421 in words is "two trillion, one hundred twenty-three billion, three hundred forty-three million, one hundred twenty thousand, four hundred twenty-one".