201664 has 28 divisors (see below), whose sum is σ = 420624. Its totient is φ = 95744.

The previous prime is 201661. The next prime is 201667. The reversal of 201664 is 466102.

201664 is nontrivially palindromic in base 7.

It is an interprime number because it is at equal distance from previous prime (201661) and next prime (201667).

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1404 + ... + 1540.

2²⁰¹⁶⁶⁴ 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 201664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210312).

201664 is an abundant number, since it is smaller than the sum of its proper divisors (218960).

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

201664 is a wasteful number, since it uses less digits than its factorization.

201664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 201664 is about 449.0701504220. The cubic root of 201664 is about 58.6420925546.

Adding to 201664 its reverse (466102), we get a palindrome (667766).

It can be divided in two parts, 2016 and 64, that added together give a triangular number (2080 = T₆₄).

The spelling of 201664 in words is "two hundred one thousand, six hundred sixty-four".