66549664 has 24 divisors (see below), whose sum is σ = 135539460. Its totient is φ = 32126976.

The previous prime is 66549641. The next prime is 66549689. The reversal of 66549664 is 46694566.

It can be written as a sum of positive squares in 2 ways, for example, as 65739664 + 810000 = 8108^2 + 900^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34929 + ... + 36784.

Almost surely, 2^66549664 is an apocalyptic number.

It is an amenable number.

66549664 is an abundant number, since it is smaller than the sum of its proper divisors (68989796).

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

66549664 is a wasteful number, since it uses less digits than its factorization.

66549664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71752 (or 71744 counting only the distinct ones).

The product of its digits is 933120, while the sum is 46.

The square root of 66549664 is about 8157.7977420380. The cubic root of 66549664 is about 405.2427828468.

The spelling of 66549664 in words is "sixty-six million, five hundred forty-nine thousand, six hundred sixty-four".