28756530 has 96 divisors (see below), whose sum is σ = 84284928. Its totient is φ = 6739200.

The previous prime is 28756517. The next prime is 28756531. The reversal of 28756530 is 3565782.

It is not an unprimeable number, because it can be changed into a prime (28756531) 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 47 ways as a sum of consecutive naturals, for example, 30222 + ... + 31158.

It is an arithmetic number, because the mean of its divisors is an integer number (877968).

Almost surely, 2^28756530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28756530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42142464).

28756530 is an abundant number, since it is smaller than the sum of its proper divisors (55528398).

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

28756530 is a wasteful number, since it uses less digits than its factorization.

28756530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992 (or 989 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The square root of 28756530 is about 5362.5115384491. The cubic root of 28756530 is about 306.3694755272.

The spelling of 28756530 in words is "twenty-eight million, seven hundred fifty-six thousand, five hundred thirty".