28218375 has 48 divisors (see below), whose sum is σ = 52809120. Its totient is φ = 15033600.

The previous prime is 28218371. The next prime is 28218391. The reversal of 28218375 is 57381282.

28218375 is a `hidden beast` number, since 282 + 1 + 8 + 375 = 666.

It is not a de Polignac number, because 28218375 - 2² = 28218371 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28218371) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 29911 + ... + 30839.

It is an arithmetic number, because the mean of its divisors is an integer number (1100190).

Almost surely, 2^28218375 is an apocalyptic number.

28218375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28218375 is a deficient number, since it is larger than the sum of its proper divisors (24590745).

28218375 is an frugal number, since it uses more digits than its factorization.

28218375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959 (or 937 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 28218375 is about 5312.0970435413. The cubic root of 28218375 is about 304.4462765275.

The spelling of 28218375 in words is "twenty-eight million, two hundred eighteen thousand, three hundred seventy-five".