2031309 has 24 divisors (see below), whose sum is σ = 3531840. Its totient is φ = 1099008.

The previous prime is 2031301. The next prime is 2031319. The reversal of 2031309 is 9031302.

It is not a de Polignac number, because 2031309 - 2³ = 2031301 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 2031291 and 2031300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2031301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 349 + ... + 2045.

It is an arithmetic number, because the mean of its divisors is an integer number (147160).

2^2031309 is an apocalyptic number.

It is an amenable number.

2031309 is a deficient number, since it is larger than the sum of its proper divisors (1500531).

2031309 is a wasteful number, since it uses less digits than its factorization.

2031309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1729 (or 1726 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

The square root of 2031309 is about 1425.2399797929. The cubic root of 2031309 is about 126.6461516483.

It can be divided in two parts, 20 and 31309, that added together give a square (31329 = 177²).

The spelling of 2031309 in words is "two million, thirty-one thousand, three hundred nine".