18538813511 has 2 divisors, whose sum is σ = 18538813512. Its totient is φ = 18538813510.

The previous prime is 18538813373. The next prime is 18538813519. The reversal of 18538813511 is 11531883581.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18538813511 is a prime.

It is a super-2 number, since 2×18538813511² (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 (18538813519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9269406755 + 9269406756.

It is an arithmetic number, because the mean of its divisors is an integer number (9269406756).

Almost surely, 2^18538813511 is an apocalyptic number.

18538813511 is a deficient number, since it is larger than the sum of its proper divisors (1).

18538813511 is an equidigital number, since it uses as much as digits as its factorization.

18538813511 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 115200, while the sum is 44.

The spelling of 18538813511 in words is "eighteen billion, five hundred thirty-eight million, eight hundred thirteen thousand, five hundred eleven".