28504538 has 8 divisors (see below), whose sum is σ = 42793140. Its totient is φ = 14240160.

The previous prime is 28504537. The next prime is 28504559. The reversal of 28504538 is 83540582.

It can be written as a sum of positive squares in 2 ways, for example, as 27008809 + 1495729 = 5197^2 + 1223^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 28504498 and 28504507.

It is not an unprimeable number, because it can be changed into a prime (28504537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2753 + ... + 8036.

Almost surely, 2^28504538 is an apocalyptic number.

28504538 is a deficient number, since it is larger than the sum of its proper divisors (14288602).

28504538 is a wasteful number, since it uses less digits than its factorization.

28504538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12112.

The product of its (nonzero) digits is 38400, while the sum is 35.

The square root of 28504538 is about 5338.9641317394. The cubic root of 28504538 is about 305.4719487299.

The spelling of 28504538 in words is "twenty-eight million, five hundred four thousand, five hundred thirty-eight".