28399424 has 56 divisors (see below), whose sum is σ = 59070240. Its totient is φ = 13533696.

The previous prime is 28399403. The next prime is 28399447. The reversal of 28399424 is 42499382.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158567 + ... + 158745.

Almost surely, 2^28399424 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 28399424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29535120).

28399424 is an abundant number, since it is smaller than the sum of its proper divisors (30670816).

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

28399424 is a wasteful number, since it uses less digits than its factorization.

28399424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295 (or 285 counting only the distinct ones).

The product of its digits is 124416, while the sum is 41.

The square root of 28399424 is about 5329.1109952787. The cubic root of 28399424 is about 305.0959977313.

The spelling of 28399424 in words is "twenty-eight million, three hundred ninety-nine thousand, four hundred twenty-four".