28503871 has 4 divisors (see below), whose sum is σ = 31095144. Its totient is φ = 25912600.

The previous prime is 28503869. The next prime is 28503889. The reversal of 28503871 is 17830582.

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 28503871 - 2¹ = 28503869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28503841) 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, 1295620 + ... + 1295641.

It is an arithmetic number, because the mean of its divisors is an integer number (7773786).

Almost surely, 2^28503871 is an apocalyptic number.

28503871 is a deficient number, since it is larger than the sum of its proper divisors (2591273).

28503871 is a wasteful number, since it uses less digits than its factorization.

28503871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2591272.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 28503871 is about 5338.9016660733. The cubic root of 28503871 is about 305.4695660522.

Subtracting from 28503871 its reverse (17830582), we obtain a square (10673289 = 3267²).

The spelling of 28503871 in words is "twenty-eight million, five hundred three thousand, eight hundred seventy-one".