66686611 has 8 divisors (see below), whose sum is σ = 69450624. Its totient is φ = 63960960.

The previous prime is 66686569. The next prime is 66686647. The reversal of 66686611 is 11668666.

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 66686611 - 2¹⁷ = 66555539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66686651) 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, 6016 + ... + 13021.

It is an arithmetic number, because the mean of its divisors is an integer number (8681328).

Almost surely, 2^66686611 is an apocalyptic number.

66686611 is a deficient number, since it is larger than the sum of its proper divisors (2764013).

66686611 is a wasteful number, since it uses less digits than its factorization.

66686611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19181.

The product of its digits is 62208, while the sum is 40.

The square root of 66686611 is about 8166.1870539438. The cubic root of 66686611 is about 405.5205641613.

The spelling of 66686611 in words is "sixty-six million, six hundred eighty-six thousand, six hundred eleven".