18505173223 has 2 divisors, whose sum is σ = 18505173224. Its totient is φ = 18505173222.

The previous prime is 18505173173. The next prime is 18505173233. The reversal of 18505173223 is 32237150581.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18505173223 - 2²⁵ = 18471618791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18505173233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9252586611 + 9252586612.

It is an arithmetic number, because the mean of its divisors is an integer number (9252586612).

Almost surely, 2^18505173223 is an apocalyptic number.

18505173223 is a deficient number, since it is larger than the sum of its proper divisors (1).

18505173223 is an equidigital number, since it uses as much as digits as its factorization.

18505173223 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50400, while the sum is 37.

The spelling of 18505173223 in words is "eighteen billion, five hundred five million, one hundred seventy-three thousand, two hundred twenty-three".