2123111321 has 2 divisors, whose sum is σ = 2123111322. Its totient is φ = 2123111320.

The previous prime is 2123111311. The next prime is 2123111327. The reversal of 2123111321 is 1231113212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1911001225 + 212110096 = 43715^2 + 14564^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2123111321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2123111321.

It is not a weakly prime, because it can be changed into another prime (2123111327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1061555660 + 1061555661.

It is an arithmetic number, because the mean of its divisors is an integer number (1061555661).

Almost surely, 2^2123111321 is an apocalyptic number.

It is an amenable number.

2123111321 is a deficient number, since it is larger than the sum of its proper divisors (1).

2123111321 is an equidigital number, since it uses as much as digits as its factorization.

2123111321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 17.

The square root of 2123111321 is about 46077.2321325837. The cubic root of 2123111321 is about 1285.2597941522.

Adding to 2123111321 its reverse (1231113212), we get a palindrome (3354224533).

It can be divided in two parts, 2 and 123111321, that multiplied together give a palindrome (246222642).

The spelling of 2123111321 in words is "two billion, one hundred twenty-three million, one hundred eleven thousand, three hundred twenty-one".