28787905 has 8 divisors (see below), whose sum is σ = 34809984. Its totient is φ = 22854000.

The previous prime is 28787903. The next prime is 28787909. The reversal of 28787905 is 50978782.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28787905 - 2¹ = 28787903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28787903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21321 + ... + 22630.

It is an arithmetic number, because the mean of its divisors is an integer number (4351248).

Almost surely, 2^28787905 is an apocalyptic number.

It is an amenable number.

28787905 is a deficient number, since it is larger than the sum of its proper divisors (6022079).

28787905 is a wasteful number, since it uses less digits than its factorization.

28787905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44087.

The product of its (nonzero) digits is 282240, while the sum is 46.

The square root of 28787905 is about 5365.4361425703. The cubic root of 28787905 is about 306.4808571687.

It can be divided in two parts, 28787 and 905, that added together give a palindrome (29692).

The spelling of 28787905 in words is "twenty-eight million, seven hundred eighty-seven thousand, nine hundred five".