18240646013 has 2 divisors, whose sum is σ = 18240646014. Its totient is φ = 18240646012.

The previous prime is 18240646001. The next prime is 18240646027. The reversal of 18240646013 is 31064604281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18051803449 + 188842564 = 134357^2 + 13742^2 .

It is a cyclic number.

It is not a de Polignac number, because 18240646013 - 2⁸ = 18240645757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18240643013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9120323006 + 9120323007.

It is an arithmetic number, because the mean of its divisors is an integer number (9120323007).

Almost surely, 2^18240646013 is an apocalyptic number.

It is an amenable number.

18240646013 is a deficient number, since it is larger than the sum of its proper divisors (1).

18240646013 is an equidigital number, since it uses as much as digits as its factorization.

18240646013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 35.

The spelling of 18240646013 in words is "eighteen billion, two hundred forty million, six hundred forty-six thousand, thirteen".