1666131775 has 48 divisors (see below), whose sum is σ = 2600190720. Its totient is φ = 1028793600.

The previous prime is 1666131769. The next prime is 1666131781. The reversal of 1666131775 is 5771316661.

It is an interprime number because it is at equal distance from previous prime (1666131769) and next prime (1666131781).

It is not a de Polignac number, because 1666131775 - 2⁵ = 1666131743 is a prime.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 201931 + ... + 210019.

It is an arithmetic number, because the mean of its divisors is an integer number (54170640).

Almost surely, 2^1666131775 is an apocalyptic number.

1666131775 is a deficient number, since it is larger than the sum of its proper divisors (934058945).

1666131775 is a wasteful number, since it uses less digits than its factorization.

1666131775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8224 (or 8219 counting only the distinct ones).

The product of its digits is 158760, while the sum is 43.

The square root of 1666131775 is about 40818.2774624310. The cubic root of 1666131775 is about 1185.5042510863.

The spelling of 1666131775 in words is "one billion, six hundred sixty-six million, one hundred thirty-one thousand, seven hundred seventy-five".