28408 has 16 divisors (see below), whose sum is σ = 55080. Its totient is φ = 13728.

The previous prime is 28403. The next prime is 28409. The reversal of 28408 is 80482.

28408 is nontrivially palindromic in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28403) 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, 391 + ... + 457.

2²⁸⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

28408 is a deficient number, since it is larger than the sum of its proper divisors (26672).

28408 is a wasteful number, since it uses less digits than its factorization.

28408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 28408 is about 168.5467294254. The cubic root of 28408 is about 30.5126705396.

Adding to 28408 its product of nonzero digits (512), we get a triangular number (28920 = T₂₄₀).

The spelling of 28408 in words is "twenty-eight thousand, four hundred eight".