12771938169 has 45 divisors (see below), whose sum is σ = 19805392893. Its totient is φ = 8202031488.

The previous prime is 12771938087. The next prime is 12771938171. The reversal of 12771938169 is 96183917721.

It is a happy number.

The square root of 12771938169 is 113013.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 2119221225 + 10652716944 = 46035^2 + 103212^2 .

It is not a de Polignac number, because 12771938169 - 2⁹ = 12771937657 is a prime.

It is a super-2 number, since 2×12771938169² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (12771933169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 29496177 + ... + 29496609.

Almost surely, 2^12771938169 is an apocalyptic number.

12771938169 is the 113013-rd square number.

12771938169 is the 56507-th centered octagonal number.

It is an amenable number.

12771938169 is a deficient number, since it is larger than the sum of its proper divisors (7033454724).

12771938169 is an frugal number, since it uses more digits than its factorization.

12771938169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 936 (or 465 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 54.

The spelling of 12771938169 in words is "twelve billion, seven hundred seventy-one million, nine hundred thirty-eight thousand, one hundred sixty-nine".