6389440 has 56 divisors (see below), whose sum is σ = 15617952. Its totient is φ = 2488320.

The previous prime is 6389431. The next prime is 6389443. The reversal of 6389440 is 449836.

It is a junction number, because it is equal to n+sod(n) for n = 6389396 and 6389405.

It is not an unprimeable number, because it can be changed into a prime (6389443) 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, 12877 + ... + 13363.

It is an arithmetic number, because the mean of its divisors is an integer number (278892).

Almost surely, 2^6389440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6389440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7808976).

6389440 is an abundant number, since it is smaller than the sum of its proper divisors (9228512).

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

6389440 is a wasteful number, since it uses less digits than its factorization.

6389440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 6389440 is about 2527.7341632379. The cubic root of 6389440 is about 185.5613821754.

The spelling of 6389440 in words is "six million, three hundred eighty-nine thousand, four hundred forty".