28715775 has 24 divisors (see below), whose sum is σ = 51794304. Its totient is φ = 13922400.

The previous prime is 28715749. The next prime is 28715777. The reversal of 28715775 is 57751782.

It is not a de Polignac number, because 28715775 - 2⁶ = 28715711 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28715777) 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 23 ways as a sum of consecutive naturals, for example, 16579 + ... + 18228.

It is an arithmetic number, because the mean of its divisors is an integer number (2158096).

Almost surely, 2^28715775 is an apocalyptic number.

28715775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28715775 is a deficient number, since it is larger than the sum of its proper divisors (23078529).

28715775 is a wasteful number, since it uses less digits than its factorization.

28715775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34831 (or 34826 counting only the distinct ones).

The product of its digits is 137200, while the sum is 42.

The square root of 28715775 is about 5358.7101992924. The cubic root of 28715775 is about 306.2246737351.

It can be divided in two parts, 2871 and 5775, that added together give a triangular number (8646 = T₁₃₁).

The spelling of 28715775 in words is "twenty-eight million, seven hundred fifteen thousand, seven hundred seventy-five".