201655216566 has 24 divisors (see below), whose sum is σ = 451013818944. Its totient is φ = 65050069680.

The previous prime is 201655216561. The next prime is 201655216573. The reversal of 201655216566 is 665612556102.

201655216566 is a `hidden beast` number, since 2 + 0 + 1 + 6 + 5 + 521 + 65 + 66 = 666.

201655216566 is digitally balanced in base 3, 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 (201655216561) 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 11 ways as a sum of consecutive naturals, for example, 180694081 + ... + 180695196.

It is an arithmetic number, because the mean of its divisors is an integer number (18792242456).

Almost surely, 2^201655216566 is an apocalyptic number.

201655216566 is an abundant number, since it is smaller than the sum of its proper divisors (249358602378).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

201655216566 is a wasteful number, since it uses less digits than its factorization.

201655216566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361389316 (or 361389313 counting only the distinct ones).

The product of its (nonzero) digits is 648000, while the sum is 45.

The spelling of 201655216566 in words is "two hundred one billion, six hundred fifty-five million, two hundred sixteen thousand, five hundred sixty-six".