201668533685 has 4 divisors (see below), whose sum is σ = 242002240428. Its totient is φ = 161334826944.

The previous prime is 201668533681. The next prime is 201668533727. The reversal of 201668533685 is 586335866102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84169034161 + 117499499524 = 290119^2 + 342782^2 .

It is a cyclic number.

It is not a de Polignac number, because 201668533685 - 2² = 201668533681 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201668533681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20166853364 + ... + 20166853373.

It is an arithmetic number, because the mean of its divisors is an integer number (60500560107).

Almost surely, 2^201668533685 is an apocalyptic number.

It is an amenable number.

201668533685 is a deficient number, since it is larger than the sum of its proper divisors (40333706743).

201668533685 is an equidigital number, since it uses as much as digits as its factorization.

201668533685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40333706742.

The product of its (nonzero) digits is 6220800, while the sum is 53.

The spelling of 201668533685 in words is "two hundred one billion, six hundred sixty-eight million, five hundred thirty-three thousand, six hundred eighty-five".