27768384221 has 2 divisors, whose sum is σ = 27768384222. Its totient is φ = 27768384220.

The previous prime is 27768384029. The next prime is 27768384247. The reversal of 27768384221 is 12248386772.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27642720121 + 125664100 = 166261^2 + 11210^2 .

It is a cyclic number.

It is not a de Polignac number, because 27768384221 - 2¹⁰ = 27768383197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27768384221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27768384251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13884192110 + 13884192111.

It is an arithmetic number, because the mean of its divisors is an integer number (13884192111).

Almost surely, 2^27768384221 is an apocalyptic number.

It is an amenable number.

27768384221 is a deficient number, since it is larger than the sum of its proper divisors (1).

27768384221 is an equidigital number, since it uses as much as digits as its factorization.

27768384221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1806336, while the sum is 50.

The spelling of 27768384221 in words is "twenty-seven billion, seven hundred sixty-eight million, three hundred eighty-four thousand, two hundred twenty-one".