66611666 has 32 divisors (see below), whose sum is σ = 113762880. Its totient is φ = 28974400.

The previous prime is 66611651. The next prime is 66611669.

66611666 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×66611666² = 8874228094591112, which contains 22 as substring.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66611669) 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, 83180 + ... + 83976.

It is an arithmetic number, because the mean of its divisors is an integer number (3555090).

Almost surely, 2^66611666 is an apocalyptic number.

66611666 is a deficient number, since it is larger than the sum of its proper divisors (47151214).

66611666 is a wasteful number, since it uses less digits than its factorization.

66611666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 970.

The product of its digits is 46656, while the sum is 38.

The square root of 66611666 is about 8161.5970250926. The cubic root of 66611666 is about 405.3685939708.

The spelling of 66611666 in words is "sixty-six million, six hundred eleven thousand, six hundred sixty-six".