66688636 has 12 divisors (see below), whose sum is σ = 133377328. Its totient is φ = 28580832.

The previous prime is 66688631. The next prime is 66688669. The reversal of 66688636 is 63688666.

66688636 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 66688636.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66688631) by changing a digit.

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, 1190841 + ... + 1190896.

Almost surely, 2^66688636 is an apocalyptic number.

It is an amenable number.

66688636 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

66688636 is a wasteful number, since it uses less digits than its factorization.

66688636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2381748 (or 2381746 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 49.

The square root of 66688636 is about 8166.3110398760. The cubic root of 66688636 is about 405.5246687875.

The spelling of 66688636 in words is "sixty-six million, six hundred eighty-eight thousand, six hundred thirty-six".