320640564 has 24 divisors (see below), whose sum is σ = 772296448. Its totient is φ = 103432320.

The previous prime is 320640563. The next prime is 320640569. The reversal of 320640564 is 465046023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320640563) 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 in 7 ways as a sum of consecutive naturals, for example, 430597 + ... + 431340.

Almost surely, 2^320640564 is an apocalyptic number.

It is an amenable number.

320640564 is an abundant number, since it is smaller than the sum of its proper divisors (451655884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

320640564 is a wasteful number, since it uses less digits than its factorization.

320640564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 861975 (or 861973 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 320640564 is about 17906.4391770112. The cubic root of 320640564 is about 684.4464699073.

Adding to 320640564 its reverse (465046023), we get a palindrome (785686587).

The spelling of 320640564 in words is "three hundred twenty million, six hundred forty thousand, five hundred sixty-four".