18914536691 has 2 divisors, whose sum is σ = 18914536692. Its totient is φ = 18914536690.

The previous prime is 18914536681. The next prime is 18914536763. The reversal of 18914536691 is 19663541981.

It is a weak prime.

It is an emirp because it is prime and its reverse (19663541981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18914536691 - 2¹⁰ = 18914535667 is a prime.

It is not a weakly prime, because it can be changed into another prime (18914536621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9457268345 + 9457268346.

It is an arithmetic number, because the mean of its divisors is an integer number (9457268346).

Almost surely, 2^18914536691 is an apocalyptic number.

18914536691 is a deficient number, since it is larger than the sum of its proper divisors (1).

18914536691 is an equidigital number, since it uses as much as digits as its factorization.

18914536691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1399680, while the sum is 53.

The spelling of 18914536691 in words is "eighteen billion, nine hundred fourteen million, five hundred thirty-six thousand, six hundred ninety-one".