28404864 has 64 divisors (see below), whose sum is σ = 83844000. Its totient is φ = 9467136.

The previous prime is 28404853. The next prime is 28404881. The reversal of 28404864 is 46840482.

It is a tau number, because it is divible by the number of its divisors (64).

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

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 654 + ... + 7565.

Almost surely, 2^28404864 is an apocalyptic number.

28404864 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 28404864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41922000).

28404864 is an abundant number, since it is smaller than the sum of its proper divisors (55439136).

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

28404864 is an equidigital number, since it uses as much as digits as its factorization.

28404864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8242 (or 8224 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 36.

The square root of 28404864 is about 5329.6213749196. The cubic root of 28404864 is about 305.1154771905.

The spelling of 28404864 in words is "twenty-eight million, four hundred four thousand, eight hundred sixty-four".