28204407 has 24 divisors (see below), whose sum is σ = 50793600. Its totient is φ = 14651280.

The previous prime is 28204391. The next prime is 28204409. The reversal of 28204407 is 70440282.

It is not a de Polignac number, because 28204407 - 2⁴ = 28204391 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28204409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19657 + ... + 21042.

It is an arithmetic number, because the mean of its divisors is an integer number (2116400).

Almost surely, 2^28204407 is an apocalyptic number.

28204407 is a deficient number, since it is larger than the sum of its proper divisors (22589193).

28204407 is a wasteful number, since it uses less digits than its factorization.

28204407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40723 (or 40720 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 28204407 is about 5310.7821457861. The cubic root of 28204407 is about 304.3960349451.

Adding to 28204407 its reverse (70440282), we get a palindrome (98644689).

It can be divided in two parts, 2820 and 4407, that added together give a palindrome (7227).

The spelling of 28204407 in words is "twenty-eight million, two hundred four thousand, four hundred seven".