231909 has 8 divisors (see below), whose sum is σ = 322752. Its totient is φ = 147840.

The previous prime is 231901. The next prime is 231919. The reversal of 231909 is 909132.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 231909 - 2³ = 231901 is a prime.

231909 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1612 + ... + 1749.

It is an arithmetic number, because the mean of its divisors is an integer number (40344).

2²³¹⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

231909 is a deficient number, since it is larger than the sum of its proper divisors (90843).

231909 is a wasteful number, since it uses less digits than its factorization.

231909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3387.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 231909 is about 481.5693096533. The cubic root of 231909 is about 61.4383015311.

The spelling of 231909 in words is "two hundred thirty-one thousand, nine hundred nine".