18104987 has 2 divisors, whose sum is σ = 18104988. Its totient is φ = 18104986.

The previous prime is 18104939. The next prime is 18105007. The reversal of 18104987 is 78940181.

It is a strong prime.

It is an emirp because it is prime and its reverse (78940181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18104987 - 2⁶ = 18104923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18104987.

It is not a weakly prime, because it can be changed into another prime (18104927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9052493 + 9052494.

It is an arithmetic number, because the mean of its divisors is an integer number (9052494).

Almost surely, 2^18104987 is an apocalyptic number.

18104987 is a deficient number, since it is larger than the sum of its proper divisors (1).

18104987 is an equidigital number, since it uses as much as digits as its factorization.

18104987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 18104987 is about 4254.9955346628. The cubic root of 18104987 is about 262.5826775095.

Adding to 18104987 its sum of digits (38), we get a square (18105025 = 4255²).

It can be divided in two parts, 18104 and 987, that added together give a palindrome (19091).

The spelling of 18104987 in words is "eighteen million, one hundred four thousand, nine hundred eighty-seven".