28885405 has 8 divisors (see below), whose sum is σ = 34782552. Its totient is φ = 23028288.

The previous prime is 28885403. The next prime is 28885433. The reversal of 28885405 is 50458882.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3048516 + 25836889 = 1746^2 + 5083^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28885405 - 2¹ = 28885403 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 (28885403) 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 7 ways as a sum of consecutive naturals, for example, 8394 + ... + 11323.

It is an arithmetic number, because the mean of its divisors is an integer number (4347819).

Almost surely, 2^28885405 is an apocalyptic number.

It is an amenable number.

28885405 is a deficient number, since it is larger than the sum of its proper divisors (5897147).

28885405 is a wasteful number, since it uses less digits than its factorization.

28885405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20015.

The product of its (nonzero) digits is 102400, while the sum is 40.

The square root of 28885405 is about 5374.5143966688. The cubic root of 28885405 is about 306.8264677282.

The spelling of 28885405 in words is "twenty-eight million, eight hundred eighty-five thousand, four hundred five".