28358728 has 8 divisors (see below), whose sum is σ = 53172630. Its totient is φ = 14179360.

The previous prime is 28358689. The next prime is 28358731. The reversal of 28358728 is 82785382.

It can be written as a sum of positive squares in only one way, i.e., 22297284 + 6061444 = 4722^2 + 2462^2 .

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, 1772413 + ... + 1772428.

Almost surely, 2^28358728 is an apocalyptic number.

It is an amenable number.

28358728 is a deficient number, since it is larger than the sum of its proper divisors (24813902).

28358728 is a wasteful number, since it uses less digits than its factorization.

28358728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3544847 (or 3544843 counting only the distinct ones).

The product of its digits is 215040, while the sum is 43.

The square root of 28358728 is about 5325.2913535317. The cubic root of 28358728 is about 304.9501952180.

The spelling of 28358728 in words is "twenty-eight million, three hundred fifty-eight thousand, seven hundred twenty-eight".