28776005 has 6 divisors (see below), whose sum is σ = 34545606. Its totient is φ = 23011208.

The previous prime is 28776001. The next prime is 28776023. The reversal of 28776005 is 50067782.

It can be written as a sum of positive squares in only one way, i.e., 23020804 + 5755201 = 4798^2 + 2399^2 .

It is not a de Polignac number, because 28776005 - 2² = 28776001 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 (28776001) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 10796 + ... + 13194.

It is an arithmetic number, because the mean of its divisors is an integer number (5757601).

Almost surely, 2^28776005 is an apocalyptic number.

It is an amenable number.

28776005 is a deficient number, since it is larger than the sum of its proper divisors (5769601).

28776005 is an frugal number, since it uses more digits than its factorization.

28776005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4803 (or 2404 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 28776005 is about 5364.3270780220. The cubic root of 28776005 is about 306.4386215510.

The spelling of 28776005 in words is "twenty-eight million, seven hundred seventy-six thousand, five".