6403728 has 40 divisors (see below), whose sum is σ = 16740000. Its totient is φ = 2109184.

The previous prime is 6403723. The next prime is 6403739. The reversal of 6403728 is 8273046.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 6403695 and 6403704.

It is not an unprimeable number, because it can be changed into a prime (6403723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3523 + ... + 5021.

It is an arithmetic number, because the mean of its divisors is an integer number (418500).

Almost surely, 2^6403728 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 6403728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8370000).

6403728 is an abundant number, since it is smaller than the sum of its proper divisors (10336272).

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

6403728 is a wasteful number, since it uses less digits than its factorization.

6403728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1599 (or 1593 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 6403728 is about 2530.5588315627. The cubic root of 6403728 is about 185.6995960204.

The spelling of 6403728 in words is "six million, four hundred three thousand, seven hundred twenty-eight".