27117721 has 4 divisors (see below), whose sum is σ = 27163444. Its totient is φ = 27072000.

The previous prime is 27117719. The next prime is 27117743. The reversal of 27117721 is 12771172.

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 10634121 + 16483600 = 3261^2 + 4060^2 .

It is a cyclic number.

It is not a de Polignac number, because 27117721 - 2¹ = 27117719 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27117721.

It is not an unprimeable number, because it can be changed into a prime (27117751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21960 + ... + 23161.

It is an arithmetic number, because the mean of its divisors is an integer number (6790861).

Almost surely, 2^27117721 is an apocalyptic number.

It is an amenable number.

27117721 is a deficient number, since it is larger than the sum of its proper divisors (45723).

27117721 is an equidigital number, since it uses as much as digits as its factorization.

27117721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45722.

The product of its digits is 1372, while the sum is 28.

The square root of 27117721 is about 5207.4678107502. The cubic root of 27117721 is about 300.4353715700.

Adding to 27117721 its reverse (12771172), we get a palindrome (39888893).

The spelling of 27117721 in words is "twenty-seven million, one hundred seventeen thousand, seven hundred twenty-one".