8161664661618 has 64 divisors (see below), whose sum is σ = 17868090868992. Its totient is φ = 2469982798080.

The previous prime is 8161664661611. The next prime is 8161664661673.

8161664661618 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×8161664661618² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (8161664661611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129114796 + ... + 129177992.

It is an arithmetic number, because the mean of its divisors is an integer number (279188919828).

Almost surely, 2^{8161664661618} is an apocalyptic number.

8161664661618 is an abundant number, since it is smaller than the sum of its proper divisors (9706426207374).

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

8161664661618 is a wasteful number, since it uses less digits than its factorization.

8161664661618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90419.

The product of its digits is 11943936, while the sum is 60.

The spelling of 8161664661618 in words is "eight trillion, one hundred sixty-one billion, six hundred sixty-four million, six hundred sixty-one thousand, six hundred eighteen".