320513021 has 2 divisors, whose sum is σ = 320513022. Its totient is φ = 320513020.

The previous prime is 320513003. The next prime is 320513047. The reversal of 320513021 is 120315023.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 265233796 + 55279225 = 16286^2 + 7435^2 .

It is a cyclic number.

It is not a de Polignac number, because 320513021 - 2¹⁴ = 320496637 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (320513051) 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, 160256510 + 160256511.

It is an arithmetic number, because the mean of its divisors is an integer number (160256511).

Almost surely, 2^320513021 is an apocalyptic number.

It is an amenable number.

320513021 is a deficient number, since it is larger than the sum of its proper divisors (1).

320513021 is an equidigital number, since it uses as much as digits as its factorization.

320513021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 320513021 is about 17902.8774502871. The cubic root of 320513021 is about 684.3557058314.

Adding to 320513021 its reverse (120315023), we get a palindrome (440828044).

The spelling of 320513021 in words is "three hundred twenty million, five hundred thirteen thousand, twenty-one".