18194012549 has 2 divisors, whose sum is σ = 18194012550. Its totient is φ = 18194012548.

The previous prime is 18194012537. The next prime is 18194012579. The reversal of 18194012549 is 94521049181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12262240225 + 5931772324 = 110735^2 + 77018^2 .

It is a cyclic number.

It is not a de Polignac number, because 18194012549 - 2¹² = 18194008453 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18194012579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9097006274 + 9097006275.

It is an arithmetic number, because the mean of its divisors is an integer number (9097006275).

Almost surely, 2^18194012549 is an apocalyptic number.

It is an amenable number.

18194012549 is a deficient number, since it is larger than the sum of its proper divisors (1).

18194012549 is an equidigital number, since it uses as much as digits as its factorization.

18194012549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 44.

The spelling of 18194012549 in words is "eighteen billion, one hundred ninety-four million, twelve thousand, five hundred forty-nine".