12640442069 has 2 divisors, whose sum is σ = 12640442070. Its totient is φ = 12640442068.

The previous prime is 12640442041. The next prime is 12640442161. The reversal of 12640442069 is 96024404621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10467949969 + 2172492100 = 102313^2 + 46610^2 .

It is an emirp because it is prime and its reverse (96024404621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12640442069 - 2¹⁶ = 12640376533 is a prime.

It is a super-2 number, since 2×12640442069² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12640442029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6320221034 + 6320221035.

It is an arithmetic number, because the mean of its divisors is an integer number (6320221035).

Almost surely, 2^12640442069 is an apocalyptic number.

It is an amenable number.

12640442069 is a deficient number, since it is larger than the sum of its proper divisors (1).

12640442069 is an equidigital number, since it uses as much as digits as its factorization.

12640442069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 82944, while the sum is 38.

The spelling of 12640442069 in words is "twelve billion, six hundred forty million, four hundred forty-two thousand, sixty-nine".