231109 has 2 divisors, whose sum is σ = 231110. Its totient is φ = 231108.

The previous prime is 231107. The next prime is 231131. The reversal of 231109 is 901132.

231109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216225 + 14884 = 465^2 + 122^2 .

It is a cyclic number.

It is not a de Polignac number, because 231109 - 2¹ = 231107 is a prime.

It is a super-2 number, since 2×231109² = 106822739762, which contains 22 as substring.

Together with 231107, it forms a pair of twin primes.

It is an Ulam number.

231109 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 231092 and 231101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115554 + 115555.

It is an arithmetic number, because the mean of its divisors is an integer number (115555).

2²³¹¹⁰⁹ is an apocalyptic number.

It is an amenable number.

231109 is a deficient number, since it is larger than the sum of its proper divisors (1).

231109 is an equidigital number, since it uses as much as digits as its factorization.

231109 is an odious number, because the sum of its binary digits is odd.

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

The square root of 231109 is about 480.7379743686. The cubic root of 231109 is about 61.3675736926.

The spelling of 231109 in words is "two hundred thirty-one thousand, one hundred nine".