28131875 has 40 divisors (see below), whose sum is σ = 38987520. Its totient is φ = 20196000.

The previous prime is 28131871. The next prime is 28131881. The reversal of 28131875 is 57813182.

It is not a de Polignac number, because 28131875 - 2² = 28131871 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28131871) 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 39 ways as a sum of consecutive naturals, for example, 273074 + ... + 273176.

It is an arithmetic number, because the mean of its divisors is an integer number (974688).

Almost surely, 2^28131875 is an apocalyptic number.

28131875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28131875 is a deficient number, since it is larger than the sum of its proper divisors (10855645).

28131875 is a wasteful number, since it uses less digits than its factorization.

28131875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 150 counting only the distinct ones).

The product of its digits is 13440, while the sum is 35.

The square root of 28131875 is about 5303.9490005090. The cubic root of 28131875 is about 304.1348771014.

The spelling of 28131875 in words is "twenty-eight million, one hundred thirty-one thousand, eight hundred seventy-five".