28191884 has 12 divisors (see below), whose sum is σ = 56383824. Its totient is φ = 12082224.

The previous prime is 28191853. The next prime is 28191893. The reversal of 28191884 is 48819182.

28191884 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503399 + ... + 503454.

It is an arithmetic number, because the mean of its divisors is an integer number (4698652).

Almost surely, 2^28191884 is an apocalyptic number.

It is an amenable number.

28191884 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28191884 is a wasteful number, since it uses less digits than its factorization.

28191884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006864 (or 1006862 counting only the distinct ones).

The product of its digits is 36864, while the sum is 41.

The square root of 28191884 is about 5309.6029983418. The cubic root of 28191884 is about 304.3509767873.

The spelling of 28191884 in words is "twenty-eight million, one hundred ninety-one thousand, eight hundred eighty-four".