18556763198401 has 16 divisors (see below), whose sum is σ = 19133419567104. Its totient is φ = 17989385375104.

The previous prime is 18556763198387. The next prime is 18556763198443. The reversal of 18556763198401 is 10489136765581.

It is not a de Polignac number, because 18556763198401 - 2²³ = 18556754809793 is a prime.

It is a super-2 number, since 2×18556763198401² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18556763198101) 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 15 ways as a sum of consecutive naturals, for example, 2099836 + ... + 6443821.

It is an arithmetic number, because the mean of its divisors is an integer number (1195838722944).

Almost surely, 2^{18556763198401} is an apocalyptic number.

It is an amenable number.

18556763198401 is a deficient number, since it is larger than the sum of its proper divisors (576656368703).

18556763198401 is a wasteful number, since it uses less digits than its factorization.

18556763198401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8544200.

The product of its (nonzero) digits is 43545600, while the sum is 64.

The spelling of 18556763198401 in words is "eighteen trillion, five hundred fifty-six billion, seven hundred sixty-three million, one hundred ninety-eight thousand, four hundred one".