18133661664 has 72 divisors (see below), whose sum is σ = 51773255352. Its totient is φ = 6020448000.

The previous prime is 18133661653. The next prime is 18133661687. The reversal of 18133661664 is 46616633181.

18133661664 is a `hidden beast` number, since 18 + 13 + 3 + 6 + 616 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 53139 + ... + 197714.

It is an arithmetic number, because the mean of its divisors is an integer number (719072991).

Almost surely, 2^18133661664 is an apocalyptic number.

It is an amenable number.

18133661664 is an abundant number, since it is smaller than the sum of its proper divisors (33639593688).

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

18133661664 is a wasteful number, since it uses less digits than its factorization.

18133661664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251120 (or 251109 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The spelling of 18133661664 in words is "eighteen billion, one hundred thirty-three million, six hundred sixty-one thousand, six hundred sixty-four".