6564820 has 24 divisors (see below), whose sum is σ = 14014728. Its totient is φ = 2582400.

The previous prime is 6564809. The next prime is 6564827. The reversal of 6564820 is 284656.

It can be written as a sum of positive squares in 4 ways, for example, as 31684 + 6533136 = 178^2 + 2556^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6564827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1471 + ... + 3910.

It is an arithmetic number, because the mean of its divisors is an integer number (583947).

Almost surely, 2^6564820 is an apocalyptic number.

It is an amenable number.

6564820 is an abundant number, since it is smaller than the sum of its proper divisors (7449908).

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

6564820 is a wasteful number, since it uses less digits than its factorization.

6564820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5451 (or 5449 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 6564820 is about 2562.1904691104. The cubic root of 6564820 is about 187.2438695369.

It can be divided in two parts, 656 and 4820, that added together give a square (5476 = 74²).

The spelling of 6564820 in words is "six million, five hundred sixty-four thousand, eight hundred twenty".