1666606673 has 8 divisors (see below), whose sum is σ = 1689098880. Its totient is φ = 1644149520.

The previous prime is 1666606639. The next prime is 1666606687. The reversal of 1666606673 is 3766066661.

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

It is a cyclic number.

It is not a de Polignac number, because 1666606673 - 2¹² = 1666602577 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1666606693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95183 + ... + 111323.

It is an arithmetic number, because the mean of its divisors is an integer number (211137360).

Almost surely, 2^1666606673 is an apocalyptic number.

It is an amenable number.

1666606673 is a deficient number, since it is larger than the sum of its proper divisors (22492207).

1666606673 is a wasteful number, since it uses less digits than its factorization.

1666606673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17527.

The product of its (nonzero) digits is 979776, while the sum is 47.

The square root of 1666606673 is about 40824.0942704183. The cubic root of 1666606673 is about 1185.6168752546.

The spelling of 1666606673 in words is "one billion, six hundred sixty-six million, six hundred six thousand, six hundred seventy-three".