28403871 has 4 divisors (see below), whose sum is σ = 37871832. Its totient is φ = 18935912.

The previous prime is 28403863. The next prime is 28403929. The reversal of 28403871 is 17830482.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28403871 - 2³ = 28403863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28403171) 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, 4733976 + ... + 4733981.

It is an arithmetic number, because the mean of its divisors is an integer number (9467958).

Almost surely, 2^28403871 is an apocalyptic number.

28403871 is a deficient number, since it is larger than the sum of its proper divisors (9467961).

28403871 is an equidigital number, since it uses as much as digits as its factorization.

28403871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9467960.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 28403871 is about 5329.5282155178. The cubic root of 28403871 is about 305.1119216587. Note that the first 3 decimals are identical.

The spelling of 28403871 in words is "twenty-eight million, four hundred three thousand, eight hundred seventy-one".