201687 has 16 divisors (see below), whose sum is σ = 291840. Its totient is φ = 123552.

The previous prime is 201683. The next prime is 201701. The reversal of 201687 is 786102.

It is not a de Polignac number, because 201687 - 2² = 201683 is a prime.

201687 is a lucky number.

It is a nialpdrome in base 12.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 201687.

It is not an unprimeable number, because it can be changed into a prime (201683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2514 + ... + 2592.

It is an arithmetic number, because the mean of its divisors is an integer number (18240).

2²⁰¹⁶⁸⁷ is an apocalyptic number.

201687 is a deficient number, since it is larger than the sum of its proper divisors (90153).

201687 is a wasteful number, since it uses less digits than its factorization.

201687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 201687 is about 449.0957581630. The cubic root of 201687 is about 58.6443218681.

Adding to 201687 its reverse (786102), we get a palindrome (987789).

It can be divided in two parts, 201 and 687, that added together give a palindrome (888).

The spelling of 201687 in words is "two hundred one thousand, six hundred eighty-seven".