27090905 has 4 divisors (see below), whose sum is σ = 32509092. Its totient is φ = 21672720.

The previous prime is 27090881. The next prime is 27090991. The reversal of 27090905 is 50909072.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11888704 + 15202201 = 3448^2 + 3899^2 .

It is not a de Polignac number, because 27090905 - 2¹⁴ = 27074521 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 2709086 + ... + 2709095.

It is an arithmetic number, because the mean of its divisors is an integer number (8127273).

Almost surely, 2^27090905 is an apocalyptic number.

It is an amenable number.

27090905 is a deficient number, since it is larger than the sum of its proper divisors (5418187).

27090905 is an equidigital number, since it uses as much as digits as its factorization.

27090905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5418186.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 27090905 is about 5204.8924100312. The cubic root of 27090905 is about 300.3363080340.

Adding to 27090905 its reverse (50909072), we get a palindrome (77999977).

It can be divided in two parts, 2 and 7090905, that added together give a palindrome (7090907).

The spelling of 27090905 in words is "twenty-seven million, ninety thousand, nine hundred five".