66821168 has 20 divisors (see below), whose sum is σ = 130086168. Its totient is φ = 33250560.

The previous prime is 66821143. The next prime is 66821171. The reversal of 66821168 is 86112866.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6521 + ... + 13272.

Almost surely, 2^66821168 is an apocalyptic number.

It is an amenable number.

66821168 is a deficient number, since it is larger than the sum of its proper divisors (63265000).

66821168 is a wasteful number, since it uses less digits than its factorization.

66821168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20012 (or 20006 counting only the distinct ones).

The product of its digits is 27648, while the sum is 38.

The square root of 66821168 is about 8174.4215697504. The cubic root of 66821168 is about 405.7931274783.

The spelling of 66821168 in words is "sixty-six million, eight hundred twenty-one thousand, one hundred sixty-eight".