28530404 has 24 divisors (see below), whose sum is σ = 58605120. Its totient is φ = 11896416.

The previous prime is 28530391. The next prime is 28530407. The reversal of 28530404 is 40403582.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28530407) 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, 12734 + ... + 14805.

It is an arithmetic number, because the mean of its divisors is an integer number (2441880).

Almost surely, 2^28530404 is an apocalyptic number.

It is an amenable number.

28530404 is an abundant number, since it is smaller than the sum of its proper divisors (30074716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28530404 is a wasteful number, since it uses less digits than its factorization.

28530404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27587 (or 27585 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 28530404 is about 5341.3859624633. The cubic root of 28530404 is about 305.5643193862.

Adding to 28530404 its reverse (40403582), we get a palindrome (68933986).

The spelling of 28530404 in words is "twenty-eight million, five hundred thirty thousand, four hundred four".