28509028 has 6 divisors (see below), whose sum is σ = 49890806. Its totient is φ = 14254512.

The previous prime is 28509011. The next prime is 28509049. The reversal of 28509028 is 82090582.

It can be written as a sum of positive squares in only one way, i.e., 18472804 + 10036224 = 4298^2 + 3168^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28508984 and 28509002.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3563625 + ... + 3563632.

Almost surely, 2^28509028 is an apocalyptic number.

It is an amenable number.

28509028 is a deficient number, since it is larger than the sum of its proper divisors (21381778).

28509028 is a wasteful number, since it uses less digits than its factorization.

28509028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7127261 (or 7127259 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 28509028 is about 5339.3846087354. The cubic root of 28509028 is about 305.4879870772.

The spelling of 28509028 in words is "twenty-eight million, five hundred nine thousand, twenty-eight".