18221661592 has 8 divisors (see below), whose sum is σ = 34165615500. Its totient is φ = 9110830792.

The previous prime is 18221661587. The next prime is 18221661593. The reversal of 18221661592 is 29516612281.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18221661593) 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 as a sum of consecutive naturals, namely, 1138853842 + ... + 1138853857.

Almost surely, 2^18221661592 is an apocalyptic number.

It is an amenable number.

18221661592 is a deficient number, since it is larger than the sum of its proper divisors (15943953908).

18221661592 is a wasteful number, since it uses less digits than its factorization.

18221661592 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2277707705 (or 2277707701 counting only the distinct ones).

The product of its digits is 103680, while the sum is 43.

The spelling of 18221661592 in words is "eighteen billion, two hundred twenty-one million, six hundred sixty-one thousand, five hundred ninety-two".