28905001 has 4 divisors (see below), whose sum is σ = 28923732. Its totient is φ = 28886272.

The previous prime is 28904977. The next prime is 28905053. The reversal of 28905001 is 10050982.

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 18696976 + 10208025 = 4324^2 + 3195^2 .

It is a cyclic number.

It is not a de Polignac number, because 28905001 - 2⁵ = 28904969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28902001) 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, 6820 + ... + 10213.

It is an arithmetic number, because the mean of its divisors is an integer number (7230933).

Almost surely, 2^28905001 is an apocalyptic number.

It is an amenable number.

28905001 is a deficient number, since it is larger than the sum of its proper divisors (18731).

28905001 is a wasteful number, since it uses less digits than its factorization.

28905001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18730.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 28905001 is about 5376.3371360063. The cubic root of 28905001 is about 306.8958362359.

Adding to 28905001 its reverse (10050982), we get a palindrome (38955983).

The spelling of 28905001 in words is "twenty-eight million, nine hundred five thousand, one".