28178215 has 12 divisors (see below), whose sum is σ = 36616104. Its totient is φ = 20807904.

The previous prime is 28178207. The next prime is 28178233. The reversal of 28178215 is 51287182.

It is not a de Polignac number, because 28178215 - 2³ = 28178207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15829 + ... + 17518.

It is an arithmetic number, because the mean of its divisors is an integer number (3051342).

Almost surely, 2^28178215 is an apocalyptic number.

28178215 is a deficient number, since it is larger than the sum of its proper divisors (8437889).

28178215 is a wasteful number, since it uses less digits than its factorization.

28178215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33378 (or 33365 counting only the distinct ones).

The product of its digits is 8960, while the sum is 34.

The square root of 28178215 is about 5308.3156462290. The cubic root of 28178215 is about 304.3017800510.

The spelling of 28178215 in words is "twenty-eight million, one hundred seventy-eight thousand, two hundred fifteen".