2123123121 has 24 divisors (see below), whose sum is σ = 3539550144. Its totient is φ = 1201197600.

The previous prime is 2123123063. The next prime is 2123123143. The reversal of 2123123121 is 1213213212.

2123123121 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2123123121 - 2⁹ = 2123122609 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2123123094 and 2123123103.

It is not an unprimeable number, because it can be changed into a prime (2123123221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 160471 + ... + 173196.

It is an arithmetic number, because the mean of its divisors is an integer number (147481256).

Almost surely, 2^2123123121 is an apocalyptic number.

2123123121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2123123121 is a deficient number, since it is larger than the sum of its proper divisors (1416427023).

2123123121 is a wasteful number, since it uses less digits than its factorization.

2123123121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333781 (or 333778 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 2123123121 is about 46077.3601782915. The cubic root of 2123123121 is about 1285.2621752548.

Adding to 2123123121 its reverse (1213213212), we get a palindrome (3336336333).

Subtracting from 2123123121 its reverse (1213213212), we obtain a palindrome (909909909).

The spelling of 2123123121 in words is "two billion, one hundred twenty-three million, one hundred twenty-three thousand, one hundred twenty-one".