665452117561 has 8 divisors (see below), whose sum is σ = 829654588224. Its totient is φ = 518534117520.

The previous prime is 665452117513. The next prime is 665452117601. The reversal of 665452117561 is 165711254566.

665452117561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 665452117561 - 2⁹ = 665452117049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665452117501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4321117570 + ... + 4321117723.

It is an arithmetic number, because the mean of its divisors is an integer number (103706823528).

Almost surely, 2^665452117561 is an apocalyptic number.

It is an amenable number.

665452117561 is a deficient number, since it is larger than the sum of its proper divisors (164202470663).

665452117561 is a wasteful number, since it uses less digits than its factorization.

665452117561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8642235311.

The product of its digits is 1512000, while the sum is 49.

The spelling of 665452117561 in words is "six hundred sixty-five billion, four hundred fifty-two million, one hundred seventeen thousand, five hundred sixty-one".