28980785 has 4 divisors (see below), whose sum is σ = 34776948. Its totient is φ = 23184624.

The previous prime is 28980769. The next prime is 28980799. The reversal of 28980785 is 58708982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58708982 = 2 ⋅29354491.

It can be written as a sum of positive squares in 2 ways, for example, as 10764961 + 18215824 = 3281^2 + 4268^2 .

It is a cyclic number.

It is not a de Polignac number, because 28980785 - 2⁴ = 28980769 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 (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2898074 + ... + 2898083.

It is an arithmetic number, because the mean of its divisors is an integer number (8694237).

Almost surely, 2^28980785 is an apocalyptic number.

It is an amenable number.

28980785 is a deficient number, since it is larger than the sum of its proper divisors (5796163).

28980785 is an equidigital number, since it uses as much as digits as its factorization.

28980785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5796162.

The product of its (nonzero) digits is 322560, while the sum is 47.

The square root of 28980785 is about 5383.3804435503. The cubic root of 28980785 is about 307.1638117512.

The spelling of 28980785 in words is "twenty-eight million, nine hundred eighty thousand, seven hundred eighty-five".