804421728 has 144 divisors (see below), whose sum is σ = 2576351232. Its totient is φ = 235872000.

The previous prime is 804421669. The next prime is 804421729. The reversal of 804421728 is 827124408.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 804421692 and 804421701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (804421729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94113 + ... + 102303.

It is an arithmetic number, because the mean of its divisors is an integer number (17891328).

Almost surely, 2^804421728 is an apocalyptic number.

804421728 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 804421728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1288175616).

804421728 is an abundant number, since it is smaller than the sum of its proper divisors (1771929504).

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

804421728 is a wasteful number, since it uses less digits than its factorization.

804421728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8249 (or 8238 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 36.

The square root of 804421728 is about 28362.3293824749. The cubic root of 804421728 is about 930.0249455674.

The spelling of 804421728 in words is "eight hundred four million, four hundred twenty-one thousand, seven hundred twenty-eight".