28533987 has 12 divisors (see below), whose sum is σ = 41617264. Its totient is φ = 18837360.

The previous prime is 28533959. The next prime is 28534001. The reversal of 28533987 is 78933582.

28533987 is a `hidden beast` number, since 28 + 533 + 98 + 7 = 666.

It is not a de Polignac number, because 28533987 - 2⁷ = 28533859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28533907) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14464 + ... + 16317.

Almost surely, 2^28533987 is an apocalyptic number.

28533987 is a deficient number, since it is larger than the sum of its proper divisors (13083277).

28533987 is a wasteful number, since it uses less digits than its factorization.

28533987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30890 (or 30887 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 28533987 is about 5341.7213517742. The cubic root of 28533987 is about 305.5771103154.

The spelling of 28533987 in words is "twenty-eight million, five hundred thirty-three thousand, nine hundred eighty-seven".