28711328 has 12 divisors (see below), whose sum is σ = 56525490. Its totient is φ = 14355648.

The previous prime is 28711307. The next prime is 28711339. The reversal of 28711328 is 82311782.

It can be written as a sum of positive squares in only one way, i.e., 28601104 + 110224 = 5348^2 + 332^2 .

It is a Harshad number since it is a multiple of its sum of digits (32), and also a Moran number because the ratio is a prime number: 897229 = 28711328 / (2 + 8 + 7 + 1 + 1 + 3 + 2 + 8).

It is a junction number, because it is equal to n+sod(n) for n = 28711294 and 28711303.

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, 448583 + ... + 448646.

Almost surely, 2^28711328 is an apocalyptic number.

It is an amenable number.

28711328 is a deficient number, since it is larger than the sum of its proper divisors (27814162).

28711328 is an equidigital number, since it uses as much as digits as its factorization.

28711328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 897239 (or 897231 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 28711328 is about 5358.2952512903. The cubic root of 28711328 is about 306.2088653345.

The spelling of 28711328 in words is "twenty-eight million, seven hundred eleven thousand, three hundred twenty-eight".