12643954061 has 2 divisors, whose sum is σ = 12643954062. Its totient is φ = 12643954060.

The previous prime is 12643954027. The next prime is 12643954109. The reversal of 12643954061 is 16045934621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8736453961 + 3907500100 = 93469^2 + 62510^2 .

It is a cyclic number.

It is not a de Polignac number, because 12643954061 - 2³⁰ = 11570212237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12643954261) 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 as a sum of consecutive naturals, namely, 6321977030 + 6321977031.

It is an arithmetic number, because the mean of its divisors is an integer number (6321977031).

Almost surely, 2^12643954061 is an apocalyptic number.

It is an amenable number.

12643954061 is a deficient number, since it is larger than the sum of its proper divisors (1).

12643954061 is an equidigital number, since it uses as much as digits as its factorization.

12643954061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 41.

The spelling of 12643954061 in words is "twelve billion, six hundred forty-three million, nine hundred fifty-four thousand, sixty-one".