18174921749 has 2 divisors, whose sum is σ = 18174921750. Its totient is φ = 18174921748.

The previous prime is 18174921691. The next prime is 18174921767. The reversal of 18174921749 is 94712947181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15903732100 + 2271189649 = 126110^2 + 47657^2 .

It is a cyclic number.

It is not a de Polignac number, because 18174921749 - 2²⁰ = 18173873173 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 18174921749.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18174921649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9087460874 + 9087460875.

It is an arithmetic number, because the mean of its divisors is an integer number (9087460875).

Almost surely, 2^18174921749 is an apocalyptic number.

It is an amenable number.

18174921749 is a deficient number, since it is larger than the sum of its proper divisors (1).

18174921749 is an equidigital number, since it uses as much as digits as its factorization.

18174921749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1016064, while the sum is 53.

The spelling of 18174921749 in words is "eighteen billion, one hundred seventy-four million, nine hundred twenty-one thousand, seven hundred forty-nine".