201868533666 has 64 divisors (see below), whose sum is σ = 459433434240. Its totient is φ = 65666764800.

The previous prime is 201868533637. The next prime is 201868533677. The reversal of 201868533666 is 666335868102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2639566 + ... + 2714966.

It is an arithmetic number, because the mean of its divisors is an integer number (7178647410).

Almost surely, 2^201868533666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201868533666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229716717120).

201868533666 is an abundant number, since it is smaller than the sum of its proper divisors (257564900574).

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

201868533666 is a wasteful number, since it uses less digits than its factorization.

201868533666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76608 (or 76602 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 54.

The spelling of 201868533666 in words is "two hundred one billion, eight hundred sixty-eight million, five hundred thirty-three thousand, six hundred sixty-six".