28788191 has 16 divisors (see below), whose sum is σ = 31606848. Its totient is φ = 26112000.

The previous prime is 28788187. The next prime is 28788223. The reversal of 28788191 is 19188782.

It is not a de Polignac number, because 28788191 - 2² = 28788187 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 (28788101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71591 + ... + 71991.

It is an arithmetic number, because the mean of its divisors is an integer number (1975428).

Almost surely, 2^28788191 is an apocalyptic number.

28788191 is a deficient number, since it is larger than the sum of its proper divisors (2818657).

28788191 is a wasteful number, since it uses less digits than its factorization.

28788191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562.

The product of its digits is 64512, while the sum is 44.

The square root of 28788191 is about 5365.4627945779. The cubic root of 28788191 is about 306.4818720999.

The spelling of 28788191 in words is "twenty-eight million, seven hundred eighty-eight thousand, one hundred ninety-one".