66809668 has 24 divisors (see below), whose sum is σ = 119508480. Its totient is φ = 32672640.

The previous prime is 66809599. The next prime is 66809671. The reversal of 66809668 is 86690866.

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 7 ways as a sum of consecutive naturals, for example, 34773 + ... + 36643.

It is an arithmetic number, because the mean of its divisors is an integer number (4979520).

Almost surely, 2^66809668 is an apocalyptic number.

It is an amenable number.

66809668 is a deficient number, since it is larger than the sum of its proper divisors (52698812).

66809668 is a wasteful number, since it uses less digits than its factorization.

66809668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2067 (or 2065 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 49.

The square root of 66809668 is about 8173.7181257981. The cubic root of 66809668 is about 405.7698469878.

The spelling of 66809668 in words is "sixty-six million, eight hundred nine thousand, six hundred sixty-eight".