66639711 has 8 divisors (see below), whose sum is σ = 94079664. Its totient is φ = 41813120.

The previous prime is 66639667. The next prime is 66639751. The reversal of 66639711 is 11793666.

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 66639711 - 2⁶ = 66639647 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66639711.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66639751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 653280 + ... + 653381.

It is an arithmetic number, because the mean of its divisors is an integer number (11759958).

Almost surely, 2^66639711 is an apocalyptic number.

66639711 is a deficient number, since it is larger than the sum of its proper divisors (27439953).

66639711 is a wasteful number, since it uses less digits than its factorization.

66639711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1306681.

The product of its digits is 40824, while the sum is 39.

The square root of 66639711 is about 8163.3149516603. The cubic root of 66639711 is about 405.4254757344.

The spelling of 66639711 in words is "sixty-six million, six hundred thirty-nine thousand, seven hundred eleven".