1323211921 has 2 divisors, whose sum is σ = 1323211922. Its totient is φ = 1323211920.

The previous prime is 1323211837. The next prime is 1323211937. The reversal of 1323211921 is 1291123231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1320304896 + 2907025 = 36336^2 + 1705^2 .

It is a cyclic number.

It is not a de Polignac number, because 1323211921 - 2²⁵ = 1289657489 is a prime.

It is not a weakly prime, because it can be changed into another prime (1323211991) 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, 661605960 + 661605961.

It is an arithmetic number, because the mean of its divisors is an integer number (661605961).

Almost surely, 2^1323211921 is an apocalyptic number.

It is an amenable number.

1323211921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1323211921 is an equidigital number, since it uses as much as digits as its factorization.

1323211921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 25.

The square root of 1323211921 is about 36375.9800005443. The cubic root of 1323211921 is about 1097.8503254274.

The spelling of 1323211921 in words is "one billion, three hundred twenty-three million, two hundred eleven thousand, nine hundred twenty-one".