564644500661 has 4 divisors (see below), whose sum is σ = 582858839424. Its totient is φ = 546430161900.

The previous prime is 564644500573. The next prime is 564644500727. The reversal of 564644500661 is 166005446465.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 564644500661 - 2¹⁰ = 564644499637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (564644500061) 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 3 ways as a sum of consecutive naturals, for example, 9107169335 + ... + 9107169396.

It is an arithmetic number, because the mean of its divisors is an integer number (145714709856).

Almost surely, 2^564644500661 is an apocalyptic number.

It is an amenable number.

564644500661 is a deficient number, since it is larger than the sum of its proper divisors (18214338763).

564644500661 is a wasteful number, since it uses less digits than its factorization.

564644500661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18214338762.

The product of its (nonzero) digits is 2073600, while the sum is 47.

The spelling of 564644500661 in words is "five hundred sixty-four billion, six hundred forty-four million, five hundred thousand, six hundred sixty-one".