27318218021 has 4 divisors (see below), whose sum is σ = 27358570572. Its totient is φ = 27277865472.

The previous prime is 27318217967. The next prime is 27318218023. The reversal of 27318218021 is 12081281372.

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 27254377921 + 63840100 = 165089^2 + 7990^2 .

It is a cyclic number.

It is not a de Polignac number, because 27318218021 - 2⁶ = 27318217957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27318218023) 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, 20175260 + ... + 20176613.

It is an arithmetic number, because the mean of its divisors is an integer number (6839642643).

Almost surely, 2^27318218021 is an apocalyptic number.

It is an amenable number.

27318218021 is a deficient number, since it is larger than the sum of its proper divisors (40352551).

27318218021 is an equidigital number, since it uses as much as digits as its factorization.

27318218021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40352550.

The product of its (nonzero) digits is 10752, while the sum is 35.

Adding to 27318218021 its reverse (12081281372), we get a palindrome (39399499393).

The spelling of 27318218021 in words is "twenty-seven billion, three hundred eighteen million, two hundred eighteen thousand, twenty-one".