6388820 has 12 divisors (see below), whose sum is σ = 13416564. Its totient is φ = 2555520.

The previous prime is 6388819. The next prime is 6388829. The reversal of 6388820 is 288836.

6388820 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 1731856 + 4656964 = 1316^2 + 2158^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6388829) 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 3 ways as a sum of consecutive naturals, for example, 159701 + ... + 159740.

It is an arithmetic number, because the mean of its divisors is an integer number (1118047).

Almost surely, 2^6388820 is an apocalyptic number.

It is an amenable number.

6388820 is an abundant number, since it is smaller than the sum of its proper divisors (7027744).

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

6388820 is a wasteful number, since it uses less digits than its factorization.

6388820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319450 (or 319448 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 35.

The square root of 6388820 is about 2527.6115207840. The cubic root of 6388820 is about 185.5553799917. Note that the first 3 decimals are identical.

The spelling of 6388820 in words is "six million, three hundred eighty-eight thousand, eight hundred twenty".