1305728 has 24 divisors (see below), whose sum is σ = 2627265. Its totient is φ = 646400.

The previous prime is 1305713. The next prime is 1305739. The reversal of 1305728 is 8275031.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 906304 + 399424 = 952^2 + 632^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=808.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1305697 and 1305706.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 12878 + ... + 12978.

2^1305728 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 1305728

1305728 is an abundant number, since it is smaller than the sum of its proper divisors (1321537).

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

1305728 is an frugal number, since it uses more digits than its factorization.

1305728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 1305728 is about 1142.6845583975. The cubic root of 1305728 is about 109.2993482845.

The spelling of 1305728 in words is "one million, three hundred five thousand, seven hundred twenty-eight".