28656663 has 32 divisors (see below), whose sum is σ = 45384192. Its totient is φ = 15744000.

The previous prime is 28656601. The next prime is 28656671. The reversal of 28656663 is 36665682.

It is not a de Polignac number, because 28656663 - 2⁶ = 28656599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28654663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71263 + ... + 71663.

It is an arithmetic number, because the mean of its divisors is an integer number (1418256).

Almost surely, 2^28656663 is an apocalyptic number.

28656663 is a deficient number, since it is larger than the sum of its proper divisors (16727529).

28656663 is a wasteful number, since it uses less digits than its factorization.

28656663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535.

The product of its digits is 311040, while the sum is 42.

The square root of 28656663 is about 5353.1918515966. The cubic root of 28656663 is about 306.0144061738.

The spelling of 28656663 in words is "twenty-eight million, six hundred fifty-six thousand, six hundred sixty-three".