12640547009 has 2 divisors, whose sum is σ = 12640547010. Its totient is φ = 12640547008.

The previous prime is 12640546991. The next prime is 12640547071. The reversal of 12640547009 is 90074504621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7442857984 + 5197689025 = 86272^2 + 72095^2 .

It is a cyclic number.

It is not a de Polignac number, because 12640547009 - 2²⁴ = 12623769793 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (12640547809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6320273504 + 6320273505.

It is an arithmetic number, because the mean of its divisors is an integer number (6320273505).

Almost surely, 2^12640547009 is an apocalyptic number.

It is an amenable number.

12640547009 is a deficient number, since it is larger than the sum of its proper divisors (1).

12640547009 is an equidigital number, since it uses as much as digits as its factorization.

12640547009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 12640547009 in words is "twelve billion, six hundred forty million, five hundred forty-seven thousand, nine".