9161331618 has 32 divisors (see below), whose sum is σ = 19157760000. Its totient is φ = 2915128656.

The previous prime is 9161331611. The next prime is 9161331629. The reversal of 9161331618 is 8161331619.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9161331611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2343 + ... + 135381.

It is an arithmetic number, because the mean of its divisors is an integer number (598680000).

Almost surely, 2^9161331618 is an apocalyptic number.

9161331618 is an abundant number, since it is smaller than the sum of its proper divisors (9996428382).

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

9161331618 is a wasteful number, since it uses less digits than its factorization.

9161331618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133566.

The product of its digits is 23328, while the sum is 39.

The square root of 9161331618 is about 95714.8453375964. The cubic root of 9161331618 is about 2092.4392982367.

Subtracting from 9161331618 its reverse (8161331619), we obtain a palindrome (999999999).

The spelling of 9161331618 in words is "nine billion, one hundred sixty-one million, three hundred thirty-one thousand, six hundred eighteen".