20320564 has 48 divisors (see below), whose sum is σ = 40372416. Its totient is φ = 8870400.

The previous prime is 20320541. The next prime is 20320577. The reversal of 20320564 is 46502302.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 179772 + ... + 179884.

It is an arithmetic number, because the mean of its divisors is an integer number (841092).

Almost surely, 2^20320564 is an apocalyptic number.

It is an amenable number.

20320564 is a deficient number, since it is larger than the sum of its proper divisors (20051852).

20320564 is a wasteful number, since it uses less digits than its factorization.

20320564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 254 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 20320564 is about 4507.8336260337. The cubic root of 20320564 is about 272.8843226230.

Adding to 20320564 its reverse (46502302), we get a palindrome (66822866).

The spelling of 20320564 in words is "twenty million, three hundred twenty thousand, five hundred sixty-four".