27808121 has 4 divisors (see below), whose sum is σ = 30336144. Its totient is φ = 25280100.

The previous prime is 27808117. The next prime is 27808133. The reversal of 27808121 is 12180872.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27808121 - 2² = 27808117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27808111) 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, 1263995 + ... + 1264016.

It is an arithmetic number, because the mean of its divisors is an integer number (7584036).

Almost surely, 2^27808121 is an apocalyptic number.

It is an amenable number.

27808121 is a deficient number, since it is larger than the sum of its proper divisors (2528023).

27808121 is a wasteful number, since it uses less digits than its factorization.

27808121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2528022.

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 27808121 is about 5273.3405920725. The cubic root of 27808121 is about 302.9636665979.

Adding to 27808121 its reverse (12180872), we get a palindrome (39988993).

It can be divided in two parts, 2780 and 8121, that added together give a palindrome (10901).

The spelling of 27808121 in words is "twenty-seven million, eight hundred eight thousand, one hundred twenty-one".