18616876661 has 2 divisors, whose sum is σ = 18616876662. Its totient is φ = 18616876660.

The previous prime is 18616876651. The next prime is 18616876709. The reversal of 18616876661 is 16667861681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14402400100 + 4214476561 = 120010^2 + 64919^2 .

It is an emirp because it is prime and its reverse (16667861681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18616876661 - 2³⁴ = 1437007477 is a prime.

It is a super-2 number, since 2×18616876661² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18616876597 and 18616876606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18616876651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9308438330 + 9308438331.

It is an arithmetic number, because the mean of its divisors is an integer number (9308438331).

Almost surely, 2^18616876661 is an apocalyptic number.

It is an amenable number.

18616876661 is a deficient number, since it is larger than the sum of its proper divisors (1).

18616876661 is an equidigital number, since it uses as much as digits as its factorization.

18616876661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3483648, while the sum is 56.

The spelling of 18616876661 in words is "eighteen billion, six hundred sixteen million, eight hundred seventy-six thousand, six hundred sixty-one".