28117863 has 12 divisors (see below), whose sum is σ = 40851720. Its totient is φ = 18635856.

The previous prime is 28117819. The next prime is 28117871. The reversal of 28117863 is 36871182.

It is not a de Polignac number, because 28117863 - 2⁹ = 28117351 is a prime.

It is a super-2 number, since 2×28117863² = 1581228439373538, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28117963) 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, 7473 + ... + 10586.

It is an arithmetic number, because the mean of its divisors is an integer number (3404310).

Almost surely, 2^28117863 is an apocalyptic number.

28117863 is a deficient number, since it is larger than the sum of its proper divisors (12733857).

28117863 is a wasteful number, since it uses less digits than its factorization.

28117863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18238 (or 18235 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 28117863 is about 5302.6279333930. The cubic root of 28117863 is about 304.0843739428.

The spelling of 28117863 in words is "twenty-eight million, one hundred seventeen thousand, eight hundred sixty-three".