561666055601 has 8 divisors (see below), whose sum is σ = 669812936064. Its totient is φ = 460496393280.

The previous prime is 561666055543. The next prime is 561666055663. The reversal of 561666055601 is 106550666165.

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

It is a de Polignac number, because none of the positive numbers 2^k-561666055601 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (561666051601) 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, 1744304360 + ... + 1744304681.

It is an arithmetic number, because the mean of its divisors is an integer number (83726617008).

Almost surely, 2^561666055601 is an apocalyptic number.

It is an amenable number.

561666055601 is a deficient number, since it is larger than the sum of its proper divisors (108146880463).

561666055601 is a wasteful number, since it uses less digits than its factorization.

561666055601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3488609071.

The product of its (nonzero) digits is 972000, while the sum is 47.

The spelling of 561666055601 in words is "five hundred sixty-one billion, six hundred sixty-six million, fifty-five thousand, six hundred one".