28432224 has 72 divisors (see below), whose sum is σ = 81375840. Its totient is φ = 9416448.

The previous prime is 28432219. The next prime is 28432241. The reversal of 28432224 is 42223482.

28432224 is a `hidden beast` number, since 2 + 8 + 432 + 224 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 77289 + ... + 77655.

It is an arithmetic number, because the mean of its divisors is an integer number (1130220).

Almost surely, 2^28432224 is an apocalyptic number.

28432224 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 28432224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40687920).

28432224 is an abundant number, since it is smaller than the sum of its proper divisors (52943616).

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

28432224 is a wasteful number, since it uses less digits than its factorization.

28432224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 652 (or 641 counting only the distinct ones).

The product of its digits is 6144, while the sum is 27.

The square root of 28432224 is about 5332.1875435885. The cubic root of 28432224 is about 305.2134097206.

The spelling of 28432224 in words is "twenty-eight million, four hundred thirty-two thousand, two hundred twenty-four".