18865799 has 2 divisors, whose sum is σ = 18865800. Its totient is φ = 18865798.

The previous prime is 18865771. The next prime is 18865813. The reversal of 18865799 is 99756881.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18865799 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18865799.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18865709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9432899 + 9432900.

It is an arithmetic number, because the mean of its divisors is an integer number (9432900).

Almost surely, 2^18865799 is an apocalyptic number.

18865799 is a deficient number, since it is larger than the sum of its proper divisors (1).

18865799 is an equidigital number, since it uses as much as digits as its factorization.

18865799 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 53.

The square root of 18865799 is about 4343.4777540584. The cubic root of 18865799 is about 266.2104304674.

The spelling of 18865799 in words is "eighteen million, eight hundred sixty-five thousand, seven hundred ninety-nine".