201688685 has 16 divisors (see below), whose sum is σ = 267001920. Its totient is φ = 145031040.

The previous prime is 201688681. The next prime is 201688733. The reversal of 201688685 is 586886102.

It is not a de Polignac number, because 201688685 - 2² = 201688681 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201688681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15707 + ... + 25496.

It is an arithmetic number, because the mean of its divisors is an integer number (16687620).

Almost surely, 2^201688685 is an apocalyptic number.

It is an amenable number.

201688685 is a deficient number, since it is larger than the sum of its proper divisors (65313235).

201688685 is a wasteful number, since it uses less digits than its factorization.

201688685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41308.

The product of its (nonzero) digits is 184320, while the sum is 44.

The square root of 201688685 is about 14201.7141571009. The cubic root of 201688685 is about 586.4448518288. Note that the first 3 decimals are identical.

It can be divided in two parts, 201 and 688685, that added together give a palindrome (688886).

The spelling of 201688685 in words is "two hundred one million, six hundred eighty-eight thousand, six hundred eighty-five".