28278105 has 8 divisors (see below), whose sum is σ = 45244992. Its totient is φ = 15081648.

The previous prime is 28278091. The next prime is 28278113. The reversal of 28278105 is 50187282.

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

It is not a de Polignac number, because 28278105 - 2⁵ = 28278073 is a prime.

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 7 ways as a sum of consecutive naturals, for example, 942589 + ... + 942618.

It is an arithmetic number, because the mean of its divisors is an integer number (5655624).

Almost surely, 2^28278105 is an apocalyptic number.

It is an amenable number.

28278105 is a deficient number, since it is larger than the sum of its proper divisors (16966887).

28278105 is a wasteful number, since it uses less digits than its factorization.

28278105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1885215.

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 28278105 is about 5317.7161451134. The cubic root of 28278105 is about 304.6609328841.

It can be divided in two parts, 282 and 78105, that added together give a palindrome (78387).

The spelling of 28278105 in words is "twenty-eight million, two hundred seventy-eight thousand, one hundred five".