66688600 has 48 divisors (see below), whose sum is σ = 169152120. Its totient is φ = 24249600.

The previous prime is 66688579. The next prime is 66688619. The reversal of 66688600 is 688666.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12957 + ... + 17356.

Almost surely, 2^66688600 is an apocalyptic number.

It is an amenable number.

66688600 is an abundant number, since it is smaller than the sum of its proper divisors (102463520).

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

66688600 is a wasteful number, since it uses less digits than its factorization.

66688600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30340 (or 30331 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 66688600 is about 8166.3088356980. The cubic root of 66688600 is about 405.5245958171.

The spelling of 66688600 in words is "sixty-six million, six hundred eighty-eight thousand, six hundred".