2121312123 has 24 divisors (see below), whose sum is σ = 3503057376. Its totient is φ = 1211760000.

The previous prime is 2121312119. The next prime is 2121312131. The reversal of 2121312123 is 3212131212.

It is not a de Polignac number, because 2121312123 - 2² = 2121312119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121312096 and 2121312105.

It is not an unprimeable number, because it can be changed into a prime (2121312143) 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, 343503 + ... + 349623.

It is an arithmetic number, because the mean of its divisors is an integer number (145960724).

Almost surely, 2^2121312123 is an apocalyptic number.

2121312123 is a deficient number, since it is larger than the sum of its proper divisors (1381745253).

2121312123 is a wasteful number, since it uses less digits than its factorization.

2121312123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11635 (or 11632 counting only the distinct ones).

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

The square root of 2121312123 is about 46057.7042740951. The cubic root of 2121312123 is about 1284.8966336734.

Adding to 2121312123 its reverse (3212131212), we get a palindrome (5333443335).

It can be divided in two parts, 212131212 and 3, that multiplied together give a palindrome (636393636).

The spelling of 2121312123 in words is "two billion, one hundred twenty-one million, three hundred twelve thousand, one hundred twenty-three".