18158640516 has 81 divisors (see below), whose sum is σ = 47252951109. Its totient is φ = 5879586528.

The previous prime is 18158640503. The next prime is 18158640517. The reversal of 18158640516 is 61504685181.

The square root of 18158640516 is 134754.

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

18158640516 is a `hidden beast` number, since 1 + 8 + 15 + 86 + 40 + 516 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16248600900 + 1910039616 = 127470^2 + 43704^2 .

It is not an unprimeable number, because it can be changed into a prime (18158640517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 29915085 + ... + 29915691.

Almost surely, 2^18158640516 is an apocalyptic number.

18158640516 is the 134754-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18158640516

18158640516 is an abundant number, since it is smaller than the sum of its proper divisors (29094310593).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18158640516 is an equidigital number, since it uses as much as digits as its factorization.

18158640516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1298 (or 649 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 45.

The spelling of 18158640516 in words is "eighteen billion, one hundred fifty-eight million, six hundred forty thousand, five hundred sixteen".