1666685017 has 4 divisors (see below), whose sum is σ = 1711730596. Its totient is φ = 1621639440.

The previous prime is 1666684993. The next prime is 1666685021. The reversal of 1666685017 is 7105866661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 965282761 + 701402256 = 31069^2 + 26484^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666685017 - 2¹⁹ = 1666160729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1666685717) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22522734 + ... + 22522807.

It is an arithmetic number, because the mean of its divisors is an integer number (427932649).

Almost surely, 2^1666685017 is an apocalyptic number.

It is an amenable number.

1666685017 is a deficient number, since it is larger than the sum of its proper divisors (45045579).

1666685017 is an equidigital number, since it uses as much as digits as its factorization.

1666685017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45045578.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 1666685017 is about 40825.0537905341. The cubic root of 1666685017 is about 1185.6354528259.

The spelling of 1666685017 in words is "one billion, six hundred sixty-six million, six hundred eighty-five thousand, seventeen".