66899866 has 32 divisors (see below), whose sum is σ = 111767040. Its totient is φ = 29780400.

The previous prime is 66899863. The next prime is 66899881.

66899866 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 66899866.

It is not an unprimeable number, because it can be changed into a prime (66899863) 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, 400515 + ... + 400681.

It is an arithmetic number, because the mean of its divisors is an integer number (3492720).

Almost surely, 2^66899866 is an apocalyptic number.

66899866 is a deficient number, since it is larger than the sum of its proper divisors (44867174).

66899866 is a wasteful number, since it uses less digits than its factorization.

66899866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450.

The product of its digits is 6718464, while the sum is 58.

The square root of 66899866 is about 8179.2338271992. The cubic root of 66899866 is about 405.9523713208.

The spelling of 66899866 in words is "sixty-six million, eight hundred ninety-nine thousand, eight hundred sixty-six".