28643884 has 6 divisors (see below), whose sum is σ = 50126804. Its totient is φ = 14321940.

The previous prime is 28643873. The next prime is 28643897. The reversal of 28643884 is 48834682.

It is a self number, because there is not a number n which added to its sum of digits gives 28643884.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 3580482 + ... + 3580489.

Almost surely, 2^28643884 is an apocalyptic number.

It is an amenable number.

28643884 is a deficient number, since it is larger than the sum of its proper divisors (21482920).

28643884 is a wasteful number, since it uses less digits than its factorization.

28643884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7160975 (or 7160973 counting only the distinct ones).

The product of its digits is 294912, while the sum is 43.

The square root of 28643884 is about 5351.9981315393. The cubic root of 28643884 is about 305.9689119314.

The spelling of 28643884 in words is "twenty-eight million, six hundred forty-three thousand, eight hundred eighty-four".