12741638921 has 12 divisors (see below), whose sum is σ = 14346870132. Its totient is φ = 11300784000.

The previous prime is 12741638909. The next prime is 12741638929. The reversal of 12741638921 is 12983614721.

It can be written as a sum of positive squares in 2 ways, for example, as 6538501321 + 6203137600 = 80861^2 + 78760^2 .

It is a de Polignac number, because none of the positive numbers 2^k-12741638921 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12741638929) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1279220 + ... + 1289141.

It is an arithmetic number, because the mean of its divisors is an integer number (1195572511).

Almost surely, 2^12741638921 is an apocalyptic number.

12741638921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12741638921 is a deficient number, since it is larger than the sum of its proper divisors (1605231211).

12741638921 is a wasteful number, since it uses less digits than its factorization.

12741638921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2568424 (or 2568413 counting only the distinct ones).

The product of its digits is 145152, while the sum is 44.

The spelling of 12741638921 in words is "twelve billion, seven hundred forty-one million, six hundred thirty-eight thousand, nine hundred twenty-one".