28730624 has 72 divisors (see below), whose sum is σ = 63098280. Its totient is φ = 12976128.

The previous prime is 28730623. The next prime is 28730633. The reversal of 28730624 is 42603782.

It can be written as a sum of positive squares in 4 ways, for example, as 1024 + 28729600 = 32^2 + 5360^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28730621) 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, 296144 + ... + 296240.

It is an arithmetic number, because the mean of its divisors is an integer number (876365).

Almost surely, 2^28730624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28730624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31549140).

28730624 is an abundant number, since it is smaller than the sum of its proper divisors (34367656).

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

28730624 is an equidigital number, since it uses as much as digits as its factorization.

28730624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 201 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 28730624 is about 5360.0955215369. The cubic root of 28730624 is about 306.2774478245.

The spelling of 28730624 in words is "twenty-eight million, seven hundred thirty thousand, six hundred twenty-four".