66684013 has 16 divisors (see below), whose sum is σ = 78826176. Its totient is φ = 55722240.

The previous prime is 66684011. The next prime is 66684019. The reversal of 66684013 is 31048666.

It is a cyclic number.

It is not a de Polignac number, because 66684013 - 2¹ = 66684011 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66684013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66684011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3895 + ... + 12187.

It is an arithmetic number, because the mean of its divisors is an integer number (4926636).

Almost surely, 2^66684013 is an apocalyptic number.

It is an amenable number.

66684013 is a deficient number, since it is larger than the sum of its proper divisors (12142163).

66684013 is a wasteful number, since it uses less digits than its factorization.

66684013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8364.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 66684013 is about 8166.0279818281. The cubic root of 66684013 is about 405.5152979562.

The spelling of 66684013 in words is "sixty-six million, six hundred eighty-four thousand, thirteen".