331009 has 4 divisors (see below), whose sum is σ = 378304. Its totient is φ = 283716.

The previous prime is 330997. The next prime is 331013. The reversal of 331009 is 900133.

It is a happy number.

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 331009 - 2¹¹ = 328961 is a prime.

It is a super-4 number, since 4×331009⁴ (a number of 23 digits) contains 4444 as substring.

It is a Duffinian number.

331009 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 330983 and 331001.

It is not an unprimeable number, because it can be changed into a prime (331099) 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, 23637 + ... + 23650.

It is an arithmetic number, because the mean of its divisors is an integer number (94576).

2³³¹⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

331009 is a deficient number, since it is larger than the sum of its proper divisors (47295).

331009 is an equidigital number, since it uses as much as digits as its factorization.

331009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47294.

The product of its (nonzero) digits is 81, while the sum is 16.

The square root of 331009 is about 575.3338161450. Note that the first 3 decimals coincide. The cubic root of 331009 is about 69.1745911148.

The spelling of 331009 in words is "three hundred thirty-one thousand, nine".