1666243733 has 32 divisors (see below), whose sum is σ = 2125585152. Its totient is φ = 1268467200.

The previous prime is 1666243693. The next prime is 1666243751. The reversal of 1666243733 is 3373426661.

It is not a de Polignac number, because 1666243733 - 2⁸ = 1666243477 is a prime.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666243783) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1146035 + ... + 1147487.

It is an arithmetic number, because the mean of its divisors is an integer number (66424536).

Almost surely, 2^1666243733 is an apocalyptic number.

It is an amenable number.

1666243733 is a deficient number, since it is larger than the sum of its proper divisors (459341419).

1666243733 is a wasteful number, since it uses less digits than its factorization.

1666243733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1805.

The product of its digits is 326592, while the sum is 41.

The square root of 1666243733 is about 40819.6488593422. The cubic root of 1666243733 is about 1185.5308043506.

The spelling of 1666243733 in words is "one billion, six hundred sixty-six million, two hundred forty-three thousand, seven hundred thirty-three".