28408897 has 4 divisors (see below), whose sum is σ = 30991536. Its totient is φ = 25826260.

The previous prime is 28408883. The next prime is 28408907. The reversal of 28408897 is 79880482.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28408897 - 2²³ = 20020289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28408847) 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, 1291303 + ... + 1291324.

It is an arithmetic number, because the mean of its divisors is an integer number (7747884).

Almost surely, 2^28408897 is an apocalyptic number.

It is an amenable number.

28408897 is a deficient number, since it is larger than the sum of its proper divisors (2582639).

28408897 is a wasteful number, since it uses less digits than its factorization.

28408897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2582638.

The product of its (nonzero) digits is 258048, while the sum is 46.

The square root of 28408897 is about 5329.9997185741. Note that the first 3 decimals coincide. The cubic root of 28408897 is about 305.1299168828.

The spelling of 28408897 in words is "twenty-eight million, four hundred eight thousand, eight hundred ninety-seven".