28688405 has 8 divisors (see below), whose sum is σ = 34519200. Its totient is φ = 22888656.

The previous prime is 28688393. The next prime is 28688419. The reversal of 28688405 is 50488682.

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 28688405 - 2⁴ = 28688389 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5675 + ... + 9464.

It is an arithmetic number, because the mean of its divisors is an integer number (4314900).

Almost surely, 2^28688405 is an apocalyptic number.

It is an amenable number.

28688405 is a deficient number, since it is larger than the sum of its proper divisors (5830795).

28688405 is a wasteful number, since it uses less digits than its factorization.

28688405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15523.

The product of its (nonzero) digits is 122880, while the sum is 41.

The square root of 28688405 is about 5356.1558043059. The cubic root of 28688405 is about 306.1273516931.

The spelling of 28688405 in words is "twenty-eight million, six hundred eighty-eight thousand, four hundred five".