312309 has 16 divisors (see below), whose sum is σ = 475200. Its totient is φ = 202608.

The previous prime is 312289. The next prime is 312311. The reversal of 312309 is 903213.

312309 is nontrivially palindromic in base 13.

It is not a de Polignac number, because 312309 - 2¹² = 308213 is a prime.

It is a super-2 number, since 2×312309² = 195073822962, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 312291 and 312300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (312349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1027 + ... + 1295.

It is an arithmetic number, because the mean of its divisors is an integer number (29700).

2³¹²³⁰⁹ is an apocalyptic number.

It is an amenable number.

312309 is a deficient number, since it is larger than the sum of its proper divisors (162891).

312309 is a wasteful number, since it uses less digits than its factorization.

312309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321 (or 315 counting only the distinct ones).

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

The square root of 312309 is about 558.8461326698. The cubic root of 312309 is about 67.8466121635.

The spelling of 312309 in words is "three hundred twelve thousand, three hundred nine".