28409768 has 8 divisors (see below), whose sum is σ = 53268330. Its totient is φ = 14204880.

The previous prime is 28409767. The next prime is 28409783. The reversal of 28409768 is 86790482.

It can be written as a sum of positive squares in only one way, i.e., 26399044 + 2010724 = 5138^2 + 1418^2 .

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

It is a super-2 number, since 2×28409768² = 1614229835627648, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28409767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1775603 + ... + 1775618.

Almost surely, 2^28409768 is an apocalyptic number.

It is an amenable number.

28409768 is a deficient number, since it is larger than the sum of its proper divisors (24858562).

28409768 is a wasteful number, since it uses less digits than its factorization.

28409768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3551227 (or 3551223 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 28409768 is about 5330.0814252692. The cubic root of 28409768 is about 305.1330352186.

The spelling of 28409768 in words is "twenty-eight million, four hundred nine thousand, seven hundred sixty-eight".