18666272005 has 4 divisors (see below), whose sum is σ = 22399526412. Its totient is φ = 14933017600.

The previous prime is 18666271993. The next prime is 18666272021. The reversal of 18666272005 is 50027266681.

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 9194700321 + 9471571684 = 95889^2 + 97322^2 .

It is not a de Polignac number, because 18666272005 - 2¹³ = 18666263813 is a prime.

It is a Duffinian number.

It is a congruent 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, 1866627196 + ... + 1866627205.

It is an arithmetic number, because the mean of its divisors is an integer number (5599881603).

Almost surely, 2^18666272005 is an apocalyptic number.

It is an amenable number.

18666272005 is a deficient number, since it is larger than the sum of its proper divisors (3733254407).

18666272005 is an equidigital number, since it uses as much as digits as its factorization.

18666272005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733254406.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 18666272005 in words is "eighteen billion, six hundred sixty-six million, two hundred seventy-two thousand, five".