305728 has 28 divisors (see below), whose sum is σ = 644652. Its totient is φ = 143360.

The previous prime is 305719. The next prime is 305741. The reversal of 305728 is 827503.

It can be written as a sum of positive squares in 2 ways, for example, as 222784 + 82944 = 472^2 + 288^2 .

It is an unprimeable number.

305728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 948 + ... + 1228.

2³⁰⁵⁷²⁸ 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 305728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322326).

305728 is an abundant number, since it is smaller than the sum of its proper divisors (338924).

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

305728 is a wasteful number, since it uses less digits than its factorization.

305728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310 (or 300 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 305728 is about 552.9267582601. The cubic root of 305728 is about 67.3666686770.

The spelling of 305728 in words is "three hundred five thousand, seven hundred twenty-eight".