18645473705 has 4 divisors (see below), whose sum is σ = 22374568452. Its totient is φ = 14916378960.

The previous prime is 18645473689. The next prime is 18645473713. The reversal of 18645473705 is 50737454681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14524347289 + 4121126416 = 120517^2 + 64196^2 .

It is not a de Polignac number, because 18645473705 - 2⁴ = 18645473689 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1864547366 + ... + 1864547375.

It is an arithmetic number, because the mean of its divisors is an integer number (5593642113).

Almost surely, 2^18645473705 is an apocalyptic number.

It is an amenable number.

18645473705 is a deficient number, since it is larger than the sum of its proper divisors (3729094747).

18645473705 is an equidigital number, since it uses as much as digits as its factorization.

18645473705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3729094746.

The product of its (nonzero) digits is 2822400, while the sum is 50.

The spelling of 18645473705 in words is "eighteen billion, six hundred forty-five million, four hundred seventy-three thousand, seven hundred five".