1666835001666 has 12 divisors (see below), whose sum is σ = 3611475836982. Its totient is φ = 555611667216.

The previous prime is 1666835001619. The next prime is 1666835001683. The reversal of 1666835001666 is 6661005386661.

It can be written as a sum of positive squares in only one way, i.e., 1171310517441 + 495524484225 = 1082271^2 + 703935^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 46300972251 + ... + 46300972286.

Almost surely, 2^{1666835001666} is an apocalyptic number.

1666835001666 is an abundant number, since it is smaller than the sum of its proper divisors (1944640835316).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1666835001666 is a wasteful number, since it uses less digits than its factorization.

1666835001666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92601944545 (or 92601944542 counting only the distinct ones).

The product of its (nonzero) digits is 5598720, while the sum is 54.

The spelling of 1666835001666 in words is "one trillion, six hundred sixty-six billion, eight hundred thirty-five million, one thousand, six hundred sixty-six".