28665504 has 144 divisors (see below), whose sum is σ = 95135040. Its totient is φ = 8017920.

The previous prime is 28665503. The next prime is 28665529. The reversal of 28665504 is 40556682.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×28665504² = 1643422239148032, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (28665503) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 118824 + ... + 119064.

It is an arithmetic number, because the mean of its divisors is an integer number (660660).

Almost surely, 2^28665504 is an apocalyptic number.

28665504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28665504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47567520).

28665504 is an abundant number, since it is smaller than the sum of its proper divisors (66469536).

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

28665504 is a wasteful number, since it uses less digits than its factorization.

28665504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 28665504 is about 5354.0175569380. The cubic root of 28665504 is about 306.0458729126.

The spelling of 28665504 in words is "twenty-eight million, six hundred sixty-five thousand, five hundred four".