185105993 has 2 divisors, whose sum is σ = 185105994. Its totient is φ = 185105992.

The previous prime is 185105989. The next prime is 185106007. The reversal of 185105993 is 399501581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 179479609 + 5626384 = 13397^2 + 2372^2 .

It is a cyclic number.

It is not a de Polignac number, because 185105993 - 2² = 185105989 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 185105993.

It is not a weakly prime, because it can be changed into another prime (185105933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92552996 + 92552997.

It is an arithmetic number, because the mean of its divisors is an integer number (92552997).

Almost surely, 2^185105993 is an apocalyptic number.

It is an amenable number.

185105993 is a deficient number, since it is larger than the sum of its proper divisors (1).

185105993 is an equidigital number, since it uses as much as digits as its factorization.

185105993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48600, while the sum is 41.

The square root of 185105993 is about 13605.3663309740. The cubic root of 185105993 is about 569.9107206019.

The spelling of 185105993 in words is "one hundred eighty-five million, one hundred five thousand, nine hundred ninety-three".