18209163443 has 2 divisors, whose sum is σ = 18209163444. Its totient is φ = 18209163442.

The previous prime is 18209163397. The next prime is 18209163487. The reversal of 18209163443 is 34436190281.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18209163443 is a prime.

It is a super-2 number, since 2×18209163443² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18209163443.

It is not a weakly prime, because it can be changed into another prime (18209168443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9104581721 + 9104581722.

It is an arithmetic number, because the mean of its divisors is an integer number (9104581722).

Almost surely, 2^18209163443 is an apocalyptic number.

18209163443 is a deficient number, since it is larger than the sum of its proper divisors (1).

18209163443 is an equidigital number, since it uses as much as digits as its factorization.

18209163443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 41.

The spelling of 18209163443 in words is "eighteen billion, two hundred nine million, one hundred sixty-three thousand, four hundred forty-three".