28403424 has 144 divisors (see below), whose sum is σ = 94060512. Its totient is φ = 7962624.

The previous prime is 28403393. The next prime is 28403429. The reversal of 28403424 is 42430482.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28403429) 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, 147072 + ... + 147264.

It is an arithmetic number, because the mean of its divisors is an integer number (653198).

Almost surely, 2^28403424 is an apocalyptic number.

28403424 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 28403424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47030256).

28403424 is an abundant number, since it is smaller than the sum of its proper divisors (65657088).

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

28403424 is a wasteful number, since it uses less digits than its factorization.

28403424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289 (or 278 counting only the distinct ones).

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

The square root of 28403424 is about 5329.4862791830. The cubic root of 28403424 is about 305.1103211052.

The spelling of 28403424 in words is "twenty-eight million, four hundred three thousand, four hundred twenty-four".