28785733 has 4 divisors (see below), whose sum is σ = 29040588. Its totient is φ = 28530880.

The previous prime is 28785727. The next prime is 28785737. The reversal of 28785733 is 33758782.

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 9443329 + 19342404 = 3073^2 + 4398^2 .

It is a cyclic number.

It is not a de Polignac number, because 28785733 - 2⁹ = 28785221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28785733.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28785737) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127258 + ... + 127483.

It is an arithmetic number, because the mean of its divisors is an integer number (7260147).

Almost surely, 2^28785733 is an apocalyptic number.

It is an amenable number.

28785733 is a deficient number, since it is larger than the sum of its proper divisors (254855).

28785733 is a wasteful number, since it uses less digits than its factorization.

28785733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254854.

The product of its digits is 282240, while the sum is 43.

The square root of 28785733 is about 5365.2337320941. The cubic root of 28785733 is about 306.4731491496.

The spelling of 28785733 in words is "twenty-eight million, seven hundred eighty-five thousand, seven hundred thirty-three".