18641814681 has 16 divisors (see below), whose sum is σ = 28476041600. Its totient is φ = 10626415488.

The previous prime is 18641814649. The next prime is 18641814689.

18641814681 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 18641814681 - 2⁵ = 18641814649 is a prime.

It is a super-2 number, since 2×18641814681² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18641814681.

It is not an unprimeable number, because it can be changed into a prime (18641814689) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1076626 + ... + 1093803.

It is an arithmetic number, because the mean of its divisors is an integer number (1779752600).

Almost surely, 2^18641814681 is an apocalyptic number.

It is an amenable number.

18641814681 is a deficient number, since it is larger than the sum of its proper divisors (9834226919).

18641814681 is a wasteful number, since it uses less digits than its factorization.

18641814681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2170848.

The product of its digits is 294912, while the sum is 48.

The spelling of 18641814681 in words is "eighteen billion, six hundred forty-one million, eight hundred fourteen thousand, six hundred eighty-one".