18637636013 has 2 divisors, whose sum is σ = 18637636014. Its totient is φ = 18637636012.

The previous prime is 18637636001. The next prime is 18637636051. The reversal of 18637636013 is 31063673681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13253305129 + 5384330884 = 115123^2 + 73378^2 .

It is an emirp because it is prime and its reverse (31063673681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18637636013 - 2¹² = 18637631917 is a prime.

It is a super-2 number, since 2×18637636013² (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 (18637636063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9318818006 + 9318818007.

It is an arithmetic number, because the mean of its divisors is an integer number (9318818007).

Almost surely, 2^18637636013 is an apocalyptic number.

It is an amenable number.

18637636013 is a deficient number, since it is larger than the sum of its proper divisors (1).

18637636013 is an equidigital number, since it uses as much as digits as its factorization.

18637636013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 44.

The spelling of 18637636013 in words is "eighteen billion, six hundred thirty-seven million, six hundred thirty-six thousand, thirteen".