205660561666 has 16 divisors (see below), whose sum is σ = 373299843456. Its totient is φ = 82955520576.

The previous prime is 205660561663. The next prime is 205660561693. The reversal of 205660561666 is 666165066502.

It is not an unprimeable number, because it can be changed into a prime (205660561663) 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, 432059766 + ... + 432060241.

It is an arithmetic number, because the mean of its divisors is an integer number (23331240216).

Almost surely, 2^205660561666 is an apocalyptic number.

205660561666 is a deficient number, since it is larger than the sum of its proper divisors (167639281790).

205660561666 is a wasteful number, since it uses less digits than its factorization.

205660561666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864120033.

The product of its (nonzero) digits is 2332800, while the sum is 49.

The spelling of 205660561666 in words is "two hundred five billion, six hundred sixty million, five hundred sixty-one thousand, six hundred sixty-six".