66688208 has 40 divisors (see below), whose sum is σ = 133896192. Its totient is φ = 32151168.

The previous prime is 66688207. The next prime is 66688211. The reversal of 66688208 is 80288666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66688207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74741 + ... + 75627.

Almost surely, 2^66688208 is an apocalyptic number.

It is an amenable number.

66688208 is an abundant number, since it is smaller than the sum of its proper divisors (67207984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66688208 is a wasteful number, since it uses less digits than its factorization.

66688208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059 (or 1053 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 44.

The square root of 66688208 is about 8166.2848346111. The cubic root of 66688208 is about 405.5238012487.

The spelling of 66688208 in words is "sixty-six million, six hundred eighty-eight thousand, two hundred eight".