18159718564 has 81 divisors (see below), whose sum is σ = 35388315459. Its totient is φ = 8150163840.

The previous prime is 18159718561. The next prime is 18159718571. The reversal of 18159718564 is 46581795181.

The square root of 18159718564 is 134758.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 1826878564 + 16332840000 = 42742^2 + 127800^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18159718561) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 248763232 + ... + 248763304.

Almost surely, 2^18159718564 is an apocalyptic number.

18159718564 is the 134758-th square number.

It is an amenable number.

18159718564 is a deficient number, since it is larger than the sum of its proper divisors (17228596895).

18159718564 is an equidigital number, since it uses as much as digits as its factorization.

18159718564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318 (or 159 counting only the distinct ones).

The product of its digits is 2419200, while the sum is 55.

The spelling of 18159718564 in words is "eighteen billion, one hundred fifty-nine million, seven hundred eighteen thousand, five hundred sixty-four".