1666671964 has 18 divisors (see below), whose sum is σ = 2933359800. Its totient is φ = 828575352.

The previous prime is 1666671893. The next prime is 1666671971. The reversal of 1666671964 is 4691766661.

It is a congruent number.

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, 1151089 + ... + 1152535.

Almost surely, 2^1666671964 is an apocalyptic number.

It is an amenable number.

1666671964 is a deficient number, since it is larger than the sum of its proper divisors (1266687836).

1666671964 is an equidigital number, since it uses as much as digits as its factorization.

1666671964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3097 (or 1648 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 52.

The square root of 1666671964 is about 40824.8939251531. The cubic root of 1666671964 is about 1185.6323576320.

The spelling of 1666671964 in words is "one billion, six hundred sixty-six million, six hundred seventy-one thousand, nine hundred sixty-four".