320840563 has 2 divisors, whose sum is σ = 320840564. Its totient is φ = 320840562.

The previous prime is 320840557. The next prime is 320840627. The reversal of 320840563 is 365048023.

It is a weak prime.

It is an emirp because it is prime and its reverse (365048023) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320840563 is a prime.

It is not a weakly prime, because it can be changed into another prime (320840263) 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, 160420281 + 160420282.

It is an arithmetic number, because the mean of its divisors is an integer number (160420282).

Almost surely, 2^320840563 is an apocalyptic number.

320840563 is a deficient number, since it is larger than the sum of its proper divisors (1).

320840563 is an equidigital number, since it uses as much as digits as its factorization.

320840563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 320840563 is about 17912.0228617541. The cubic root of 320840563 is about 684.5887477654.

Adding to 320840563 its reverse (365048023), we get a palindrome (685888586).

The spelling of 320840563 in words is "three hundred twenty million, eight hundred forty thousand, five hundred sixty-three".