28772224 has 32 divisors (see below), whose sum is σ = 61732440. Its totient is φ = 13278720.

The previous prime is 28772197. The next prime is 28772257. The reversal of 28772224 is 42227782.

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

It is a self number, because there is not a number n which added to its sum of digits gives 28772224.

It is a congruent number.

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 in 3 ways as a sum of consecutive naturals, for example, 6982 + ... + 10309.

Almost surely, 2^28772224 is an apocalyptic number.

It is an amenable number.

28772224 is an abundant number, since it is smaller than the sum of its proper divisors (32960216).

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

28772224 is a wasteful number, since it uses less digits than its factorization.

28772224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17318 (or 17306 counting only the distinct ones).

The product of its digits is 25088, while the sum is 34.

The square root of 28772224 is about 5363.9746457268. The cubic root of 28772224 is about 306.4251995445.

The spelling of 28772224 in words is "twenty-eight million, seven hundred seventy-two thousand, two hundred twenty-four".