2122121321 has 2 divisors, whose sum is σ = 2122121322. Its totient is φ = 2122121320.

The previous prime is 2122121303. The next prime is 2122121387. The reversal of 2122121321 is 1231212212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1394200921 + 727920400 = 37339^2 + 26980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2122121321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2122121321.

It is not a weakly prime, because it can be changed into another prime (2122127321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1061060660 + 1061060661.

It is an arithmetic number, because the mean of its divisors is an integer number (1061060661).

Almost surely, 2^2122121321 is an apocalyptic number.

It is an amenable number.

2122121321 is a deficient number, since it is larger than the sum of its proper divisors (1).

2122121321 is an equidigital number, since it uses as much as digits as its factorization.

2122121321 is an evil number, because the sum of its binary digits is even.

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

The square root of 2122121321 is about 46066.4880471694. The cubic root of 2122121321 is about 1285.0599922533.

Adding to 2122121321 its reverse (1231212212), we get a palindrome (3353333533).

The spelling of 2122121321 in words is "two billion, one hundred twenty-two million, one hundred twenty-one thousand, three hundred twenty-one".