28278618 has 8 divisors (see below), whose sum is σ = 56557248. Its totient is φ = 9426204.

The previous prime is 28278617. The next prime is 28278671. The reversal of 28278618 is 81687282.

It is a sphenic number, since it is the product of 3 distinct primes.

28278618 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 28278618.

It is not an unprimeable number, because it can be changed into a prime (28278617) 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, 2356546 + ... + 2356557.

It is an arithmetic number, because the mean of its divisors is an integer number (7069656).

Almost surely, 2^28278618 is an apocalyptic number.

28278618 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28278618 is a wasteful number, since it uses less digits than its factorization.

28278618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4713108.

The product of its digits is 86016, while the sum is 42.

The square root of 28278618 is about 5317.7643798875. The cubic root of 28278618 is about 304.6627751824.

The spelling of 28278618 in words is "twenty-eight million, two hundred seventy-eight thousand, six hundred eighteen".