201309 has 4 divisors (see below), whose sum is σ = 268416. Its totient is φ = 134204.

The previous prime is 201307. The next prime is 201329. The reversal of 201309 is 903102.

201309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 201309 - 2¹ = 201307 is a prime.

It is a D-number.

201309 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201307) 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, 33549 + ... + 33554.

It is an arithmetic number, because the mean of its divisors is an integer number (67104).

2²⁰¹³⁰⁹ is an apocalyptic number.

It is an amenable number.

201309 is a deficient number, since it is larger than the sum of its proper divisors (67107).

201309 is an equidigital number, since it uses as much as digits as its factorization.

201309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67106.

The product of its (nonzero) digits is 54, while the sum is 15.

The square root of 201309 is about 448.6747151334. The cubic root of 201309 is about 58.6076620654.

The spelling of 201309 in words is "two hundred one thousand, three hundred nine".