28667728 has 10 divisors (see below), whose sum is σ = 55543754. Its totient is φ = 14333856.

The previous prime is 28667719. The next prime is 28667801. The reversal of 28667728 is 82776682.

It can be written as a sum of positive squares in only one way, i.e., 26956864 + 1710864 = 5192^2 + 1308^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 895851 + ... + 895882.

Almost surely, 2^28667728 is an apocalyptic number.

It is an amenable number.

28667728 is a deficient number, since it is larger than the sum of its proper divisors (26876026).

28667728 is a wasteful number, since it uses less digits than its factorization.

28667728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1791741 (or 1791735 counting only the distinct ones).

The product of its digits is 451584, while the sum is 46.

The square root of 28667728 is about 5354.2252474098. The cubic root of 28667728 is about 306.0537875176.

The spelling of 28667728 in words is "twenty-eight million, six hundred sixty-seven thousand, seven hundred twenty-eight".