18865143305 has 4 divisors (see below), whose sum is σ = 22638171972. Its totient is φ = 15092114640.

The previous prime is 18865143299. The next prime is 18865143331. The reversal of 18865143305 is 50334156881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50334156881 = 177929 ⋅282889.

It can be written as a sum of positive squares in 2 ways, for example, as 3826535881 + 15038607424 = 61859^2 + 122632^2 .

It is not a de Polignac number, because 18865143305 - 2¹⁰ = 18865142281 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1886514326 + ... + 1886514335.

It is an arithmetic number, because the mean of its divisors is an integer number (5659542993).

Almost surely, 2^18865143305 is an apocalyptic number.

It is an amenable number.

18865143305 is a deficient number, since it is larger than the sum of its proper divisors (3773028667).

18865143305 is an equidigital number, since it uses as much as digits as its factorization.

18865143305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3773028666.

The product of its (nonzero) digits is 345600, while the sum is 44.

The spelling of 18865143305 in words is "eighteen billion, eight hundred sixty-five million, one hundred forty-three thousand, three hundred five".