201684 has 36 divisors (see below), whose sum is σ = 549024. Its totient is φ = 57624.

The previous prime is 201683. The next prime is 201701. The reversal of 201684 is 486102.

201684 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

201684 is a Rhonda number in base 8.

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 201684.

It is a congruent number.

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

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28809 + ... + 28815.

2²⁰¹⁶⁸⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201684, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274512).

201684 is an abundant number, since it is smaller than the sum of its proper divisors (347340).

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

201684 is an frugal number, since it uses more digits than its factorization.

201684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42 (or 12 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 201684 is about 449.0924181057. The cubic root of 201684 is about 58.6440310977.

Multiplying 201684 by its sum of digits (21), we get a square (4235364 = 2058²).

201684 divided by its sum of digits (21) gives a square (9604 = 98²).

Adding to 201684 its reverse (486102), we get a palindrome (687786).

The spelling of 201684 in words is "two hundred one thousand, six hundred eighty-four".