1668518686851 has 16 divisors (see below), whose sum is σ = 2239390498464. Its totient is φ = 1105006905344.

The previous prime is 1668518686843. The next prime is 1668518686903. The reversal of 1668518686851 is 1586868158661.

It is a cyclic number.

It is not a de Polignac number, because 1668518686851 - 2³ = 1668518686843 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1668518686811) 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, 689196 + ... + 1952441.

It is an arithmetic number, because the mean of its divisors is an integer number (139961906154).

Almost surely, 2^{1668518686851} is an apocalyptic number.

1668518686851 is a deficient number, since it is larger than the sum of its proper divisors (570871811613).

1668518686851 is a wasteful number, since it uses less digits than its factorization.

1668518686851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2643030.

The product of its digits is 132710400, while the sum is 69.

The spelling of 1668518686851 in words is "one trillion, six hundred sixty-eight billion, five hundred eighteen million, six hundred eighty-six thousand, eight hundred fifty-one".