665666168 has 8 divisors (see below), whose sum is σ = 1248124080. Its totient is φ = 332833080.

The previous prime is 665666129. The next prime is 665666171. The reversal of 665666168 is 861666566.

665666168 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×665666168² = 886222894439608448, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41604128 + ... + 41604143.

It is an arithmetic number, because the mean of its divisors is an integer number (156015510).

Almost surely, 2^665666168 is an apocalyptic number.

It is an amenable number.

665666168 is a deficient number, since it is larger than the sum of its proper divisors (582457912).

665666168 is a wasteful number, since it uses less digits than its factorization.

665666168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83208277 (or 83208273 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 50.

The square root of 665666168 is about 25800.5071267989. The cubic root of 665666168 is about 873.1432378958.

The spelling of 665666168 in words is "six hundred sixty-five million, six hundred sixty-six thousand, one hundred sixty-eight".