28775693 has 4 divisors (see below), whose sum is σ = 28814268. Its totient is φ = 28737120.

The previous prime is 28775689. The next prime is 28775699. The reversal of 28775693 is 39657782.

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

It can be written as a sum of positive squares in 2 ways, for example, as 24649 + 28751044 = 157^2 + 5362^2 .

It is a cyclic number.

It is not a de Polignac number, because 28775693 - 2² = 28775689 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28775699) 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, 18146 + ... + 19667.

It is an arithmetic number, because the mean of its divisors is an integer number (7203567).

Almost surely, 2^28775693 is an apocalyptic number.

It is an amenable number.

28775693 is a deficient number, since it is larger than the sum of its proper divisors (38575).

28775693 is an equidigital number, since it uses as much as digits as its factorization.

28775693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38574.

The product of its digits is 635040, while the sum is 47.

The square root of 28775693 is about 5364.2979969424. The cubic root of 28775693 is about 306.4375140403.

The spelling of 28775693 in words is "twenty-eight million, seven hundred seventy-five thousand, six hundred ninety-three".