320501921 has 2 divisors, whose sum is σ = 320501922. Its totient is φ = 320501920.

The previous prime is 320501903. The next prime is 320501959. The reversal of 320501921 is 129105023.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 219780625 + 100721296 = 14825^2 + 10036^2 .

It is a cyclic number.

It is not a de Polignac number, because 320501921 - 2¹⁴ = 320485537 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (320501821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160250960 + 160250961.

It is an arithmetic number, because the mean of its divisors is an integer number (160250961).

Almost surely, 2^320501921 is an apocalyptic number.

It is an amenable number.

320501921 is a deficient number, since it is larger than the sum of its proper divisors (1).

320501921 is an equidigital number, since it uses as much as digits as its factorization.

320501921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 320501921 is about 17902.5674415711. The cubic root of 320501921 is about 684.3478055428.

Adding to 320501921 its reverse (129105023), we get a palindrome (449606944).

The spelling of 320501921 in words is "three hundred twenty million, five hundred one thousand, nine hundred twenty-one".