320840560 has 20 divisors (see below), whose sum is σ = 745954488. Its totient is φ = 128336192.

The previous prime is 320840557. The next prime is 320840563. The reversal of 320840560 is 65048023.

It is an interprime number because it is at equal distance from previous prime (320840557) and next prime (320840563).

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×320840560² = 205877329882227200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320840563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2005174 + ... + 2005333.

Almost surely, 2^320840560 is an apocalyptic number.

It is an amenable number.

320840560 is an abundant number, since it is smaller than the sum of its proper divisors (425113928).

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

320840560 is a wasteful number, since it uses less digits than its factorization.

320840560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4010520 (or 4010514 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 320840560 is about 17912.0227780114. The cubic root of 320840560 is about 684.5887456317.

Adding to 320840560 its reverse (65048023), we get a palindrome (385888583).

The spelling of 320840560 in words is "three hundred twenty million, eight hundred forty thousand, five hundred sixty".