66516564 has 24 divisors (see below), whose sum is σ = 155773408. Its totient is φ = 22091040.

The previous prime is 66516559. The next prime is 66516581. The reversal of 66516564 is 46561566.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 6682 + ... + 13329.

Almost surely, 2^66516564 is an apocalyptic number.

It is an amenable number.

66516564 is an abundant number, since it is smaller than the sum of its proper divisors (89256844).

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

66516564 is a wasteful number, since it uses less digits than its factorization.

66516564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20295 (or 20293 counting only the distinct ones).

The product of its digits is 129600, while the sum is 39.

The square root of 66516564 is about 8155.7687559175. The cubic root of 66516564 is about 405.1755861110.

The spelling of 66516564 in words is "sixty-six million, five hundred sixteen thousand, five hundred sixty-four".