28009396 has 24 divisors (see below), whose sum is σ = 50496264. Its totient is φ = 13585920.

The previous prime is 28009393. The next prime is 28009427. The reversal of 28009396 is 69390082.

It can be written as a sum of positive squares in 4 ways, for example, as 1999396 + 26010000 = 1414^2 + 5100^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28009393) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37846 + ... + 38578.

It is an arithmetic number, because the mean of its divisors is an integer number (2104011).

Almost surely, 2^28009396 is an apocalyptic number.

It is an amenable number.

28009396 is a deficient number, since it is larger than the sum of its proper divisors (22486868).

28009396 is a wasteful number, since it uses less digits than its factorization.

28009396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1011 (or 1009 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 28009396 is about 5292.3903862055. The cubic root of 28009396 is about 303.6928598055.

The spelling of 28009396 in words is "twenty-eight million, nine thousand, three hundred ninety-six".