28773511 has 4 divisors (see below), whose sum is σ = 30986872. Its totient is φ = 26560152.

The previous prime is 28773509. The next prime is 28773523. The reversal of 28773511 is 11537782.

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 28773511 - 2¹ = 28773509 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 (28773551) 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 3 ways as a sum of consecutive naturals, for example, 1106661 + ... + 1106686.

It is an arithmetic number, because the mean of its divisors is an integer number (7746718).

Almost surely, 2^28773511 is an apocalyptic number.

28773511 is a deficient number, since it is larger than the sum of its proper divisors (2213361).

28773511 is a wasteful number, since it uses less digits than its factorization.

28773511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2213360.

The product of its digits is 11760, while the sum is 34.

The square root of 28773511 is about 5364.0946113953. The cubic root of 28773511 is about 306.4297683415.

The spelling of 28773511 in words is "twenty-eight million, seven hundred seventy-three thousand, five hundred eleven".