660857666 has 32 divisors (see below), whose sum is σ = 1214127360. Its totient is φ = 263583936.

The previous prime is 660857657. The next prime is 660857731. The reversal of 660857666 is 666758066.

660857666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15821 + ... + 39648.

It is an arithmetic number, because the mean of its divisors is an integer number (37941480).

Almost surely, 2^660857666 is an apocalyptic number.

660857666 is a deficient number, since it is larger than the sum of its proper divisors (553269694).

660857666 is a wasteful number, since it uses less digits than its factorization.

660857666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55538.

The product of its (nonzero) digits is 2177280, while the sum is 50.

The square root of 660857666 is about 25707.1520398507. The cubic root of 660857666 is about 871.0357444700.

The spelling of 660857666 in words is "six hundred sixty million, eight hundred fifty-seven thousand, six hundred sixty-six".