28506438 has 16 divisors (see below), whose sum is σ = 63347760. Its totient is φ = 9502128.

The previous prime is 28506437. The next prime is 28506451. The reversal of 28506438 is 83460582.

28506438 is a `hidden beast` number, since 2 + 8 + 5 + 0 + 643 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28506431) 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, 263895 + ... + 264002.

It is an arithmetic number, because the mean of its divisors is an integer number (3959235).

Almost surely, 2^28506438 is an apocalyptic number.

28506438 is an abundant number, since it is smaller than the sum of its proper divisors (34841322).

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

28506438 is a wasteful number, since it uses less digits than its factorization.

28506438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 527908 (or 527902 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 28506438 is about 5339.1420659128. The cubic root of 28506438 is about 305.4787357639.

The spelling of 28506438 in words is "twenty-eight million, five hundred six thousand, four hundred thirty-eight".