66688313 has 8 divisors (see below), whose sum is σ = 70593600. Its totient is φ = 62890128.

The previous prime is 66688291. The next prime is 66688327. The reversal of 66688313 is 31388666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66688313 - 2⁸ = 66688057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66688813) 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, 25493 + ... + 27986.

It is an arithmetic number, because the mean of its divisors is an integer number (8824200).

Almost surely, 2^66688313 is an apocalyptic number.

It is an amenable number.

66688313 is a deficient number, since it is larger than the sum of its proper divisors (3905287).

66688313 is a wasteful number, since it uses less digits than its factorization.

66688313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53551.

The product of its digits is 124416, while the sum is 41.

The square root of 66688313 is about 8166.2912634806. The cubic root of 66688313 is about 405.5240140798.

The spelling of 66688313 in words is "sixty-six million, six hundred eighty-eight thousand, three hundred thirteen".