201643 has 4 divisors (see below), whose sum is σ = 217168. Its totient is φ = 186120.

The previous prime is 201629. The next prime is 201653. The reversal of 201643 is 346102.

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

It is a cyclic number.

It is not a de Polignac number, because 201643 - 2⁵ = 201611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201623) 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, 7743 + ... + 7768.

It is an arithmetic number, because the mean of its divisors is an integer number (54292).

2²⁰¹⁶⁴³ is an apocalyptic number.

201643 is a deficient number, since it is larger than the sum of its proper divisors (15525).

201643 is a wasteful number, since it uses less digits than its factorization.

201643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15524.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 201643 is about 449.0467681656. The cubic root of 201643 is about 58.6400569463.

Adding to 201643 its reverse (346102), we get a palindrome (547745).

The spelling of 201643 in words is "two hundred one thousand, six hundred forty-three".