28565730 has 64 divisors (see below), whose sum is σ = 76665600. Its totient is φ = 7568640.

The previous prime is 28565723. The next prime is 28565731. The reversal of 28565730 is 3756582.

28565730 is a `hidden beast` number, since 2 + 85 + 6 + 573 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (28565731) 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 31 ways as a sum of consecutive naturals, for example, 64851 + ... + 65289.

It is an arithmetic number, because the mean of its divisors is an integer number (1197900).

Almost surely, 2^28565730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28565730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38332800).

28565730 is an abundant number, since it is smaller than the sum of its proper divisors (48099870).

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

28565730 is a wasteful number, since it uses less digits than its factorization.

28565730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696 (or 690 counting only the distinct ones).

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

The square root of 28565730 is about 5344.6917591195. The cubic root of 28565730 is about 305.6903827145.

The spelling of 28565730 in words is "twenty-eight million, five hundred sixty-five thousand, seven hundred thirty".