28040404 has 24 divisors (see below), whose sum is σ = 58520448. Its totient is φ = 11494560.

The previous prime is 28040387. The next prime is 28040407. The reversal of 28040404 is 40404082.

28040404 is a modest number, since divided by 40404 gives 28 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28040407) 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, 21127 + ... + 22414.

It is an arithmetic number, because the mean of its divisors is an integer number (2438352).

Almost surely, 2^28040404 is an apocalyptic number.

It is an amenable number.

28040404 is an abundant number, since it is smaller than the sum of its proper divisors (30480044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28040404 is a wasteful number, since it uses less digits than its factorization.

28040404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43575 (or 43573 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

The square root of 28040404 is about 5295.3190649856. The cubic root of 28040404 is about 303.8048869186.

Adding to 28040404 its reverse (40404082), we get a palindrome (68444486).

The spelling of 28040404 in words is "twenty-eight million, forty thousand, four hundred four".