18549473444 has 24 divisors (see below), whose sum is σ = 34204981440. Its totient is φ = 8777618784.

The previous prime is 18549473443. The next prime is 18549473473. The reversal of 18549473444 is 44437494581.

It is a super-2 number, since 2×18549473444² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18549473443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49439 + ... + 198854.

It is an arithmetic number, because the mean of its divisors is an integer number (1425207560).

Almost surely, 2^18549473444 is an apocalyptic number.

It is an amenable number.

18549473444 is a deficient number, since it is larger than the sum of its proper divisors (15655507996).

18549473444 is a wasteful number, since it uses less digits than its factorization.

18549473444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249299 (or 249297 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 53.

The spelling of 18549473444 in words is "eighteen billion, five hundred forty-nine million, four hundred seventy-three thousand, four hundred forty-four".