28440504 has 64 divisors (see below), whose sum is σ = 79437600. Its totient is φ = 9427968.

The previous prime is 28440491. The next prime is 28440521. The reversal of 28440504 is 40504482.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76062 + ... + 76434.

Almost surely, 2^28440504 is an apocalyptic number.

28440504 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 28440504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39718800).

28440504 is an abundant number, since it is smaller than the sum of its proper divisors (50997096).

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

28440504 is a wasteful number, since it uses less digits than its factorization.

28440504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741 (or 731 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

The square root of 28440504 is about 5332.9639038718. The cubic root of 28440504 is about 305.2430348126.

Adding to 28440504 its reverse (40504482), we get a palindrome (68944986).

The spelling of 28440504 in words is "twenty-eight million, four hundred forty thousand, five hundred four".