18105977 has 2 divisors, whose sum is σ = 18105978. Its totient is φ = 18105976.

The previous prime is 18105961. The next prime is 18106027. The reversal of 18105977 is 77950181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14661241 + 3444736 = 3829^2 + 1856^2 .

It is an emirp because it is prime and its reverse (77950181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18105977 - 2⁴ = 18105961 is a prime.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 18105977.

It is not a weakly prime, because it can be changed into another prime (18105937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9052988 + 9052989.

It is an arithmetic number, because the mean of its divisors is an integer number (9052989).

Almost surely, 2^18105977 is an apocalyptic number.

It is an amenable number.

18105977 is a deficient number, since it is larger than the sum of its proper divisors (1).

18105977 is an equidigital number, since it uses as much as digits as its factorization.

18105977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17640, while the sum is 38.

The square root of 18105977 is about 4255.1118669196. Note that the first 3 decimals coincide. The cubic root of 18105977 is about 262.5874635226.

The spelling of 18105977 in words is "eighteen million, one hundred five thousand, nine hundred seventy-seven".