66564886651 has 8 divisors (see below), whose sum is σ = 68893380000. Its totient is φ = 64238603520.

The previous prime is 66564886631. The next prime is 66564886693. The reversal of 66564886651 is 15668846566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66564886651 - 2²⁷ = 66430668923 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66564886651.

It is not an unprimeable number, because it can be changed into a prime (66564886631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 491151 + ... + 611848.

It is an arithmetic number, because the mean of its divisors is an integer number (8611672500).

Almost surely, 2^66564886651 is an apocalyptic number.

66564886651 is a deficient number, since it is larger than the sum of its proper divisors (2328493349).

66564886651 is a wasteful number, since it uses less digits than its factorization.

66564886651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105109.

The product of its digits is 49766400, while the sum is 61.

The spelling of 66564886651 in words is "sixty-six billion, five hundred sixty-four million, eight hundred eighty-six thousand, six hundred fifty-one".