320312211221 has 2 divisors, whose sum is σ = 320312211222. Its totient is φ = 320312211220.

The previous prime is 320312211203. The next prime is 320312211229. The reversal of 320312211221 is 122112213023.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 218958484900 + 101353726321 = 467930^2 + 318361^2 .

It is a cyclic number.

It is not a de Polignac number, because 320312211221 - 2¹⁸ = 320311949077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 320312211193 and 320312211202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (320312211229) 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, 160156105610 + 160156105611.

It is an arithmetic number, because the mean of its divisors is an integer number (160156105611).

Almost surely, 2^320312211221 is an apocalyptic number.

It is an amenable number.

320312211221 is a deficient number, since it is larger than the sum of its proper divisors (1).

320312211221 is an equidigital number, since it uses as much as digits as its factorization.

320312211221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 320312211221 its reverse (122112213023), we get a palindrome (442424424244).

The spelling of 320312211221 in words is "three hundred twenty billion, three hundred twelve million, two hundred eleven thousand, two hundred twenty-one".