12640044917 has 2 divisors, whose sum is σ = 12640044918. Its totient is φ = 12640044916.

The previous prime is 12640044883. The next prime is 12640044931. The reversal of 12640044917 is 71944004621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7542227716 + 5097817201 = 86846^2 + 71399^2 .

It is a cyclic number.

It is not a de Polignac number, because 12640044917 - 2⁶ = 12640044853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12640044517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6320022458 + 6320022459.

It is an arithmetic number, because the mean of its divisors is an integer number (6320022459).

Almost surely, 2^12640044917 is an apocalyptic number.

It is an amenable number.

12640044917 is a deficient number, since it is larger than the sum of its proper divisors (1).

12640044917 is an equidigital number, since it uses as much as digits as its factorization.

12640044917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 38.

The spelling of 12640044917 in words is "twelve billion, six hundred forty million, forty-four thousand, nine hundred seventeen".