1668666686 has 8 divisors (see below), whose sum is σ = 2561209464. Its totient is φ = 814930200.

The previous prime is 1668666683. The next prime is 1668666689. The reversal of 1668666686 is 6866668661.

It is an interprime number because it is at equal distance from previous prime (1668666683) and next prime (1668666689).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668666683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9701465 + ... + 9701636.

It is an arithmetic number, because the mean of its divisors is an integer number (320151183).

Almost surely, 2^1668666686 is an apocalyptic number.

1668666686 is a deficient number, since it is larger than the sum of its proper divisors (892542778).

1668666686 is a wasteful number, since it uses less digits than its factorization.

1668666686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19403146.

The product of its digits is 17915904, while the sum is 59.

The square root of 1668666686 is about 40849.3168363927. The cubic root of 1668666686 is about 1186.1051689435.

The spelling of 1668666686 in words is "one billion, six hundred sixty-eight million, six hundred sixty-six thousand, six hundred eighty-six".