666646620206 has 16 divisors (see below), whose sum is σ = 1142849147616. Its totient is φ = 285699101856.

The previous prime is 666646620191. The next prime is 666646620209. The reversal of 666646620206 is 602026646666.

666646620206 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666646620209) 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, 105980 + ... + 1159536.

It is an arithmetic number, because the mean of its divisors is an integer number (71428071726).

Almost surely, 2^666646620206 is an apocalyptic number.

666646620206 is a deficient number, since it is larger than the sum of its proper divisors (476202527410).

666646620206 is a wasteful number, since it uses less digits than its factorization.

666646620206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098763.

The product of its (nonzero) digits is 4478976, while the sum is 50.

The spelling of 666646620206 in words is "six hundred sixty-six billion, six hundred forty-six million, six hundred twenty thousand, two hundred six".