28394728 has 8 divisors (see below), whose sum is σ = 53240130. Its totient is φ = 14197360.

The previous prime is 28394701. The next prime is 28394761. The reversal of 28394728 is 82749382.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17623204 + 10771524 = 4198^2 + 3282^2 .

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

It is an unprimeable number.

It is a 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, 1774663 + ... + 1774678.

Almost surely, 2^28394728 is an apocalyptic number.

It is an amenable number.

28394728 is a deficient number, since it is larger than the sum of its proper divisors (24845402).

28394728 is a wasteful number, since it uses less digits than its factorization.

28394728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3549347 (or 3549343 counting only the distinct ones).

The product of its digits is 193536, while the sum is 43.

The square root of 28394728 is about 5328.6703782463. The cubic root of 28394728 is about 305.0791803740.

The spelling of 28394728 in words is "twenty-eight million, three hundred ninety-four thousand, seven hundred twenty-eight".