28785513 has 16 divisors (see below), whose sum is σ = 40801280. Its totient is φ = 18000144.

The previous prime is 28785511. The next prime is 28785517. The reversal of 28785513 is 31558782.

It is not a de Polignac number, because 28785513 - 2¹ = 28785511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28785511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3420 + ... + 8322.

It is an arithmetic number, because the mean of its divisors is an integer number (2550080).

Almost surely, 2^28785513 is an apocalyptic number.

It is an amenable number.

28785513 is a deficient number, since it is larger than the sum of its proper divisors (12015767).

28785513 is a wasteful number, since it uses less digits than its factorization.

28785513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5028.

The product of its digits is 67200, while the sum is 39.

The square root of 28785513 is about 5365.2132296862. The cubic root of 28785513 is about 306.4723683894.

The spelling of 28785513 in words is "twenty-eight million, seven hundred eighty-five thousand, five hundred thirteen".