1668518686687 has 2 divisors, whose sum is σ = 1668518686688. Its totient is φ = 1668518686686.

The previous prime is 1668518686669. The next prime is 1668518686699. The reversal of 1668518686687 is 7866868158661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1668518686687 is a prime.

It is a super-2 number, since 2×1668518686687² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668518689687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834259343343 + 834259343344.

It is an arithmetic number, because the mean of its divisors is an integer number (834259343344).

Almost surely, 2^{1668518686687} is an apocalyptic number.

1668518686687 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668518686687 is an equidigital number, since it uses as much as digits as its factorization.

1668518686687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1114767360, while the sum is 76.

The spelling of 1668518686687 in words is "one trillion, six hundred sixty-eight billion, five hundred eighteen million, six hundred eighty-six thousand, six hundred eighty-seven".