17666812643 has 2 divisors, whose sum is σ = 17666812644. Its totient is φ = 17666812642.

The previous prime is 17666812627. The next prime is 17666812679. The reversal of 17666812643 is 34621866671.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 17666812643 - 2⁴ = 17666812627 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 17666812591 and 17666812600.

It is not a weakly prime, because it can be changed into another prime (17666814643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8833406321 + 8833406322.

It is an arithmetic number, because the mean of its divisors is an integer number (8833406322).

Almost surely, 2^17666812643 is an apocalyptic number.

17666812643 is a deficient number, since it is larger than the sum of its proper divisors (1).

17666812643 is an equidigital number, since it uses as much as digits as its factorization.

17666812643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1741824, while the sum is 50.

The spelling of 17666812643 in words is "seventeen billion, six hundred sixty-six million, eight hundred twelve thousand, six hundred forty-three".