1666728604 has 12 divisors (see below), whose sum is σ = 2923024104. Its totient is φ = 831578864.

The previous prime is 1666728601. The next prime is 1666728611. The reversal of 1666728604 is 4068276661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666728601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444259 + ... + 447994.

It is an arithmetic number, because the mean of its divisors is an integer number (243585342).

Almost surely, 2^1666728604 is an apocalyptic number.

It is an amenable number.

1666728604 is a deficient number, since it is larger than the sum of its proper divisors (1256295500).

1666728604 is a wasteful number, since it uses less digits than its factorization.

1666728604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 892724 (or 892722 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 46.

The square root of 1666728604 is about 40825.5876136523. The cubic root of 1666728604 is about 1185.6457882805.

The spelling of 1666728604 in words is "one billion, six hundred sixty-six million, seven hundred twenty-eight thousand, six hundred four".