66864666 has 32 divisors (see below), whose sum is σ = 146562048. Its totient is φ = 20168240.

The previous prime is 66864647. The next prime is 66864683. The reversal of 66864666 is 66646866.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12751 + ... + 17213.

It is an arithmetic number, because the mean of its divisors is an integer number (4580064).

Almost surely, 2^66864666 is an apocalyptic number.

66864666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66864666 is an abundant number, since it is smaller than the sum of its proper divisors (79697382).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66864666 is a wasteful number, since it uses less digits than its factorization.

66864666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4706.

The product of its digits is 1492992, while the sum is 48.

The square root of 66864666 is about 8177.0817532907. The cubic root of 66864666 is about 405.8811602644.

The spelling of 66864666 in words is "sixty-six million, eight hundred sixty-four thousand, six hundred sixty-six".