66500566 has 32 divisors (see below), whose sum is σ = 115823520. Its totient is φ = 28300800.

The previous prime is 66500561. The next prime is 66500593.

66500566 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66500561) 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 15 ways as a sum of consecutive naturals, for example, 100276 + ... + 100936.

It is an arithmetic number, because the mean of its divisors is an integer number (3619485).

Almost surely, 2^66500566 is an apocalyptic number.

66500566 is a deficient number, since it is larger than the sum of its proper divisors (49322954).

66500566 is a wasteful number, since it uses less digits than its factorization.

66500566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 960.

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 66500566 is about 8154.7879187628. The cubic root of 66500566 is about 405.1431003742.

The spelling of 66500566 in words is "sixty-six million, five hundred thousand, five hundred sixty-six".