28366191 has 12 divisors (see below), whose sum is σ = 46826832. Its totient is φ = 16209216.

The previous prime is 28366189. The next prime is 28366201. The reversal of 28366191 is 19166382.

28366191 is a `hidden beast` number, since 2 + 8 + 36 + 619 + 1 = 666.

It is not a de Polignac number, because 28366191 - 2¹ = 28366189 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28366141) 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, 225066 + ... + 225191.

It is an arithmetic number, because the mean of its divisors is an integer number (3902236).

Almost surely, 2^28366191 is an apocalyptic number.

28366191 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28366191 is a deficient number, since it is larger than the sum of its proper divisors (18460641).

28366191 is a wasteful number, since it uses less digits than its factorization.

28366191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450270 (or 450267 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 28366191 is about 5325.9920202719. The cubic root of 28366191 is about 304.9769435227.

The spelling of 28366191 in words is "twenty-eight million, three hundred sixty-six thousand, one hundred ninety-one".