28403656 has 16 divisors (see below), whose sum is σ = 53747100. Its totient is φ = 14071104.

The previous prime is 28403647. The next prime is 28403671. The reversal of 28403656 is 65630482.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 26687556 + 1716100 = 5166^2 + 1310^2 .

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 3 ways as a sum of consecutive naturals, for example, 15415 + ... + 17158.

Almost surely, 2^28403656 is an apocalyptic number.

It is an amenable number.

28403656 is a deficient number, since it is larger than the sum of its proper divisors (25343444).

28403656 is a wasteful number, since it uses less digits than its factorization.

28403656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32688 (or 32684 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 28403656 is about 5329.5080448387. The cubic root of 28403656 is about 305.1111518196. Note that the first 4 decimals are identical.

The spelling of 28403656 in words is "twenty-eight million, four hundred three thousand, six hundred fifty-six".