28785115 has 4 divisors (see below), whose sum is σ = 34542144. Its totient is φ = 23028088.

The previous prime is 28785091. The next prime is 28785179. The reversal of 28785115 is 51158782.

28785115 is nontrivially palindromic in base 2.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28785115 - 2⁵ = 28785083 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2878507 + ... + 2878516.

It is an arithmetic number, because the mean of its divisors is an integer number (8635536).

Almost surely, 2^28785115 is an apocalyptic number.

28785115 is a deficient number, since it is larger than the sum of its proper divisors (5757029).

28785115 is an equidigital number, since it uses as much as digits as its factorization.

28785115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5757028.

The product of its digits is 22400, while the sum is 37.

The square root of 28785115 is about 5365.1761387675. The cubic root of 28785115 is about 306.4709559131.

Subtracting from 28785115 its sum of digits (37), we obtain a triangular number (28785078 = T₇₅₈₇).

It can be divided in two parts, 28785 and 115, that added together give a square (28900 = 170²).

The spelling of 28785115 in words is "twenty-eight million, seven hundred eighty-five thousand, one hundred fifteen".