28775628 has 96 divisors (see below), whose sum is σ = 90316800. Its totient is φ = 7734528.

The previous prime is 28775597. The next prime is 28775653. The reversal of 28775628 is 82657782.

28775628 is a `hidden beast` number, since 2 + 87 + 7 + 562 + 8 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11733 + ... + 13971.

It is an arithmetic number, because the mean of its divisors is an integer number (940800).

Almost surely, 2^28775628 is an apocalyptic number.

28775628 is a gapful number since it is divisible by the number (28) 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 28775628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45158400).

28775628 is an abundant number, since it is smaller than the sum of its proper divisors (61541172).

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

28775628 is a wasteful number, since it uses less digits than its factorization.

28775628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2276 (or 2268 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 28775628 is about 5364.2919383643. The cubic root of 28775628 is about 306.4372833079.

It can be divided in two parts, 28775 and 628, that added together give a triangular number (29403 = T₂₄₂).

The spelling of 28775628 in words is "twenty-eight million, seven hundred seventy-five thousand, six hundred twenty-eight".