18686816741745 has 12 divisors (see below), whose sum is σ = 32390482352436. Its totient is φ = 9966302262240.

The previous prime is 18686816741741. The next prime is 18686816741819. The reversal of 18686816741745 is 54714761868681.

18686816741745 is a `hidden beast` number, since 1 + 8 + 6 + 8 + 6 + 8 + 167 + 417 + 45 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7913244676401 + 10773572065344 = 2813049^2 + 3282312^2 .

It is not a de Polignac number, because 18686816741745 - 2² = 18686816741741 is a prime.

It is a super-2 number, since 2×18686816741745² (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 (18686816741741) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 207631297086 + ... + 207631297175.

It is an arithmetic number, because the mean of its divisors is an integer number (2699206862703).

Almost surely, 2^{18686816741745} is an apocalyptic number.

18686816741745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18686816741745 is a deficient number, since it is larger than the sum of its proper divisors (13703665610691).

18686816741745 is a wasteful number, since it uses less digits than its factorization.

18686816741745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415262594272 (or 415262594269 counting only the distinct ones).

The product of its digits is 433520640, while the sum is 72.

The spelling of 18686816741745 in words is "eighteen trillion, six hundred eighty-six billion, eight hundred sixteen million, seven hundred forty-one thousand, seven hundred forty-five".