389306728 has 8 divisors (see below), whose sum is σ = 729950130. Its totient is φ = 194653360.

The previous prime is 389306653. The next prime is 389306741. The reversal of 389306728 is 827603983.

It can be written as a sum of positive squares in only one way, i.e., 367795684 + 21511044 = 19178^2 + 4638^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24331663 + ... + 24331678.

Almost surely, 2^389306728 is an apocalyptic number.

It is an amenable number.

389306728 is a deficient number, since it is larger than the sum of its proper divisors (340643402).

389306728 is a wasteful number, since it uses less digits than its factorization.

389306728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48663347 (or 48663343 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 46.

The square root of 389306728 is about 19730.8572545645. The cubic root of 389306728 is about 730.1811822749.

The spelling of 389306728 in words is "three hundred eighty-nine million, three hundred six thousand, seven hundred twenty-eight".