28664532 has 72 divisors (see below), whose sum is σ = 81454464. Its totient is φ = 8433216.

The previous prime is 28664479. The next prime is 28664539. The reversal of 28664532 is 23546682.

28664532 is a `hidden beast` number, since 2 + 8 + 6 + 645 + 3 + 2 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28664539) 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 23 ways as a sum of consecutive naturals, for example, 9433 + ... + 12095.

It is an arithmetic number, because the mean of its divisors is an integer number (1131312).

Almost surely, 2^28664532 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 28664532, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40727232).

28664532 is an abundant number, since it is smaller than the sum of its proper divisors (52789932).

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

28664532 is a wasteful number, since it uses less digits than its factorization.

28664532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2709 (or 2704 counting only the distinct ones).

The product of its digits is 69120, while the sum is 36.

The square root of 28664532 is about 5353.9267832125. The cubic root of 28664532 is about 306.0424137031.

The spelling of 28664532 in words is "twenty-eight million, six hundred sixty-four thousand, five hundred thirty-two".