8405728 has 24 divisors (see below), whose sum is σ = 16618392. Its totient is φ = 4185216.

The previous prime is 8405723. The next prime is 8405759. The reversal of 8405728 is 8275048.

It is a d-powerful number, because it can be written as 8² + 4⁵ + 0 + 5⁶ + 7³ + 2²³ + 8² .

It is a junction number, because it is equal to n+sod(n) for n = 8405693 and 8405702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8405723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10726 + ... + 11482.

It is an arithmetic number, because the mean of its divisors is an integer number (692433).

Almost surely, 2^8405728 is an apocalyptic number.

It is an amenable number.

8405728 is a deficient number, since it is larger than the sum of its proper divisors (8212664).

8405728 is a wasteful number, since it uses less digits than its factorization.

8405728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1114 (or 1106 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 34.

The square root of 8405728 is about 2899.2633547162. The cubic root of 8405728 is about 203.3254665654.

The spelling of 8405728 in words is "eight million, four hundred five thousand, seven hundred twenty-eight".