18471884239449 has 27 divisors (see below), whose sum is σ = 27317363354463. Its totient is φ = 12027842667792.

The previous prime is 18471884239411. The next prime is 18471884239463. The reversal of 18471884239449 is 94493248817481.

The square root of 18471884239449 is 4297893.

It is a perfect power (a square), and thus also a powerful number.

18471884239449 is a `hidden beast` number, since 1 + 8 + 4 + 71 + 8 + 8 + 423 + 94 + 49 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5710785575625 + 12761098663824 = 2389725^2 + 3572268^2 .

It is not a de Polignac number, because 18471884239449 - 2¹⁵ = 18471884206681 is a prime.

It is a super-2 number, since 2×18471884239449² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18471884239409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 554411539 + ... + 554444855.

Almost surely, 2^{18471884239449} is an apocalyptic number.

18471884239449 is the 4297893-rd square number.

18471884239449 is the 2148947-th centered octagonal number.

It is an amenable number.

18471884239449 is a deficient number, since it is larger than the sum of its proper divisors (8845479115014).

18471884239449 is an frugal number, since it uses more digits than its factorization.

18471884239449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66726 (or 33363 counting only the distinct ones).

The product of its digits is 445906944, while the sum is 72.

The spelling of 18471884239449 in words is "eighteen trillion, four hundred seventy-one billion, eight hundred eighty-four million, two hundred thirty-nine thousand, four hundred forty-nine".