28004090 has 16 divisors (see below), whose sum is σ = 50731272. Its totient is φ = 11129664.

The previous prime is 28004089. The next prime is 28004099. The reversal of 28004090 is 9040082.

It can be written as a sum of positive squares in 4 ways, for example, as 24275329 + 3728761 = 4927^2 + 1931^2 .

It is not an unprimeable number, because it can be changed into a prime (28004099) 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, 7349 + ... + 10488.

Almost surely, 2^28004090 is an apocalyptic number.

28004090 is a deficient number, since it is larger than the sum of its proper divisors (22727182).

28004090 is a wasteful number, since it uses less digits than its factorization.

28004090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18001.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 28004090 is about 5291.8890766909. The cubic root of 28004090 is about 303.6736817640.

The spelling of 28004090 in words is "twenty-eight million, four thousand, ninety".