18442507169 has 2 divisors, whose sum is σ = 18442507170. Its totient is φ = 18442507168.

The previous prime is 18442507147. The next prime is 18442507177. The reversal of 18442507169 is 96170524481.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12469072225 + 5973434944 = 111665^2 + 77288^2 .

It is an emirp because it is prime and its reverse (96170524481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18442507169 - 2³² = 14147539873 is a prime.

It is a super-2 number, since 2×18442507169² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18442507129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9221253584 + 9221253585.

It is an arithmetic number, because the mean of its divisors is an integer number (9221253585).

Almost surely, 2^18442507169 is an apocalyptic number.

It is an amenable number.

18442507169 is a deficient number, since it is larger than the sum of its proper divisors (1).

18442507169 is an equidigital number, since it uses as much as digits as its factorization.

18442507169 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 483840, while the sum is 47.

The spelling of 18442507169 in words is "eighteen billion, four hundred forty-two million, five hundred seven thousand, one hundred sixty-nine".