1668516851685 has 16 divisors (see below), whose sum is σ = 2670045618240. Its totient is φ = 889736102400.

The previous prime is 1668516851669. The next prime is 1668516851707. The reversal of 1668516851685 is 5861586158661.

It is not a de Polignac number, because 1668516851685 - 2⁴ = 1668516851669 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8623116 + ... + 8814485.

It is an arithmetic number, because the mean of its divisors is an integer number (166877851140).

Almost surely, 2^{1668516851685} is an apocalyptic number.

1668516851685 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1668516851685 is a deficient number, since it is larger than the sum of its proper divisors (1001528766555).

1668516851685 is a wasteful number, since it uses less digits than its factorization.

1668516851685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17443988.

The product of its digits is 82944000, while the sum is 66.

The spelling of 1668516851685 in words is "one trillion, six hundred sixty-eight billion, five hundred sixteen million, eight hundred fifty-one thousand, six hundred eighty-five".