28403873 has 4 divisors (see below), whose sum is σ = 29638848. Its totient is φ = 27168900.

The previous prime is 28403863. The next prime is 28403929. The reversal of 28403873 is 37830482.

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 28403873 - 2²⁰ = 27355297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28403833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 617453 + ... + 617498.

It is an arithmetic number, because the mean of its divisors is an integer number (7409712).

Almost surely, 2^28403873 is an apocalyptic number.

28403873 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

28403873 is a deficient number, since it is larger than the sum of its proper divisors (1234975).

28403873 is a wasteful number, since it uses less digits than its factorization.

28403873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1234974.

The product of its (nonzero) digits is 32256, while the sum is 35.

The square root of 28403873 is about 5329.5284031516. The cubic root of 28403873 is about 305.1119288199. Note that the first 3 decimals are identical.

The spelling of 28403873 in words is "twenty-eight million, four hundred three thousand, eight hundred seventy-three".