18985887799 has 2 divisors, whose sum is σ = 18985887800. Its totient is φ = 18985887798.

The previous prime is 18985887751. The next prime is 18985887829. The reversal of 18985887799 is 99778858981.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (99778858981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18985887799 - 2²¹ = 18983790647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18985888799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9492943899 + 9492943900.

It is an arithmetic number, because the mean of its divisors is an integer number (9492943900).

Almost surely, 2^18985887799 is an apocalyptic number.

18985887799 is a deficient number, since it is larger than the sum of its proper divisors (1).

18985887799 is an equidigital number, since it uses as much as digits as its factorization.

18985887799 is an evil number, because the sum of its binary digits is even.

The product of its digits is 731566080, while the sum is 79.

The spelling of 18985887799 in words is "eighteen billion, nine hundred eighty-five million, eight hundred eighty-seven thousand, seven hundred ninety-nine".