66819568 has 20 divisors (see below), whose sum is σ = 130262248. Its totient is φ = 33203520.

The previous prime is 66819559. The next prime is 66819581. The reversal of 66819568 is 86591866.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 10203 + ... + 15418.

Almost surely, 2^66819568 is an apocalyptic number.

It is an amenable number.

66819568 is a deficient number, since it is larger than the sum of its proper divisors (63442680).

66819568 is a wasteful number, since it uses less digits than its factorization.

66819568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25792 (or 25786 counting only the distinct ones).

The product of its digits is 622080, while the sum is 49.

The square root of 66819568 is about 8174.3237029127. The cubic root of 66819568 is about 405.7898886135.

The spelling of 66819568 in words is "sixty-six million, eight hundred nineteen thousand, five hundred sixty-eight".