28166784 has 32 divisors (see below), whose sum is σ = 74819040. Its totient is φ = 9388800.

The previous prime is 28166783. The next prime is 28166791. The reversal of 28166784 is 48766182.

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (28166783) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 36292 + ... + 37059.

It is an arithmetic number, because the mean of its divisors is an integer number (2338095).

Almost surely, 2^28166784 is an apocalyptic number.

28166784 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28166784 is an abundant number, since it is smaller than the sum of its proper divisors (46652256).

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

28166784 is an equidigital number, since it uses as much as digits as its factorization.

28166784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73368 (or 73356 counting only the distinct ones).

The product of its digits is 129024, while the sum is 42.

The square root of 28166784 is about 5307.2388301263. The cubic root of 28166784 is about 304.2606259878.

The spelling of 28166784 in words is "twenty-eight million, one hundred sixty-six thousand, seven hundred eighty-four".