28208863 has 4 divisors (see below), whose sum is σ = 29693560. Its totient is φ = 26724168.

The previous prime is 28208857. The next prime is 28208867. The reversal of 28208863 is 36880282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36880282 = 2 ⋅18440141.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28208863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28208867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 742320 + ... + 742357.

It is an arithmetic number, because the mean of its divisors is an integer number (7423390).

Almost surely, 2^28208863 is an apocalyptic number.

28208863 is a deficient number, since it is larger than the sum of its proper divisors (1484697).

28208863 is a wasteful number, since it uses less digits than its factorization.

28208863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484696.

The product of its (nonzero) digits is 36864, while the sum is 37.

The square root of 28208863 is about 5311.2016531102. The cubic root of 28208863 is about 304.4120645595.

The spelling of 28208863 in words is "twenty-eight million, two hundred eight thousand, eight hundred sixty-three".