28756872 has 24 divisors (see below), whose sum is σ = 77883390. Its totient is φ = 9585600.

The previous prime is 28756859. The next prime is 28756873. The reversal of 28756872 is 27865782.

28756872 is a `hidden beast` number, since 2 + 87 + 568 + 7 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 24860196 + 3896676 = 4986^2 + 1974^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (28756873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 199629 + ... + 199772.

Almost surely, 2^28756872 is an apocalyptic number.

It is an amenable number.

28756872 is an abundant number, since it is smaller than the sum of its proper divisors (49126518).

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

28756872 is a wasteful number, since it uses less digits than its factorization.

28756872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399413 (or 399406 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 28756872 is about 5362.5434263976. The cubic root of 28756872 is about 306.3706900681.

Adding to 28756872 its product of digits (376320), we get a palindrome (29133192).

It can be divided in two parts, 28 and 756872, that added together give a square (756900 = 870²).

The spelling of 28756872 in words is "twenty-eight million, seven hundred fifty-six thousand, eight hundred seventy-two".