2011309 has 2 divisors, whose sum is σ = 2011310. Its totient is φ = 2011308.

The previous prime is 2011291. The next prime is 2011333. The reversal of 2011309 is 9031102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1108809 + 902500 = 1053^2 + 950^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011309 - 2⁵ = 2011277 is a prime.

It is an Ulam number.

2011309 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 2011292 and 2011301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005654 + 1005655.

It is an arithmetic number, because the mean of its divisors is an integer number (1005655).

2^2011309 is an apocalyptic number.

It is an amenable number.

2011309 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011309 is an equidigital number, since it uses as much as digits as its factorization.

2011309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 2011309 is about 1418.2062614444. The cubic root of 2011309 is about 126.2291329104.

The spelling of 2011309 in words is "two million, eleven thousand, three hundred nine".